Downsizing... Any tips on best ways to do this?

As a professional organizer and caretaker, I see you are taking a very healthy step to making your lives more stress free and bring in more time to be with him.
1.Perhaps begin by taking photos of your/ his favorite cherished items. Give this collection to whomever you believe you can trust who would be willing to make sure either of you have them in case you are not able to speak for yourself.
2. Make a list of experiences that make you and him happy ( if you become unable to speak or immobile) for example, do you like to have your arms rubbed, do you like to have your hair combed, which foods do you like to eat? do you want people to take you outside for walks? do you like small quiet places? A favorite pet? Clothing? Think of anything you can...think of your senses and what you like to smell, hear, feel, see...although with dementia, ones senses change, it always helps to have a sense of your likes and dislikes. Write down a few special moment stories with pictures people can later show you or converse with you.
3. Begin taking away items you know he will not miss and or not sentimental to either of you. ( In my experience this may be harder for you to do than one thinks because removing these things from your lives may make you feel like you are removing a part of you two, you are deceiving him, and /or having to come to terms that he is seriously ill.) Take one decision at a time.
Everyone works at this differently, however, in my experience it is often very confusing for your loved one to watch people cart things off and explaining the process to them. If they have no memory of the items, in their world, the item is already gone. They do not need to watch the process. Ask yourself, are you having them involved because you think it will make them feel included or is it because it makes you feel less guilty- yes this is very difficult, and sometimes it is good to just sit down and have a cry. No one else can be in your shoes, it is such a personal decision, it is ok to change your mind on things, or take a break.
4. Sometimes Social Services can connect you directly with a family in need. It will make the giving feel more personal and you will see a direct positive effect for someone else who is also in a hard time.
5. Removing the excess gives room for more time with precious conversations, holding their hand, and working through loss that you feel.
6. Take care of yourself. Yes, all of these things in the end are things, you and he , that connection is your "life" and moments with him are precious.
7. Begin small, moving small pebbles ( not the mountain) and over time you will start to see that tiny steps will amount to much less stress and responsibilities. You will feel the overwhelming burden of so many decisions will lighten.
8. If you are unsure of the value of items, you can hire an appraiser independently to appraise your items. If you go with a company to sell all of your items, like an estate sale, be mindful that they often charge very high prices just to even get everything ready for the sale. Often, it can be more advantageous to donate items and write them off on taxes ( places of donation will gladly pick up all of your household items- make sure you take photos first )and then you sell the few items of great value.
9. Often clients are not aware of how large their furniture is and plan on taking many oversized items with them when they downsize to another place. An easy way to guestimate what you could realistically bring when you downsize, go online, find a floorplan similar to what you have in mind on moving to later. Then measure everything you plan on taking. Will it fit into the plan? Will all of your items fit into the drawers and cabinets? Often it is better to sell/donate something you have and find items more appropriate once you are in your new residence after the excess is removed. Having more room will make staying in your current home much easier too.
You can do this. One step at a time.

I think you might be putting the cart before the horse ...
Yes, get rid of items you do not need, we should all do that. Give away items that you no longer want but others do. Sell what you can and donate what no one wants or does not sell.
But do not jump into selling his clothing and other items that he still knows and values.
You do not mention his age or the stage he is in currently but you may have many years of still washing his clothing. (My Husband was diagnosed in his early 60's and I had 12 years of the Dementia Journey.)
If the plan is that you will both move to Assisted Living sooner rather than later then I see the need to downsize a lot of things. But if you plan on staying where you are and keeping him home for as long as possible you still want your house to be your home. That means all the "stuff" that means something to you.

After cleaning out my mother’s house, and then her apartment, I KNOW I don’t want to leave things for my daughters to sort through.

One technique that is use is once a week, I fill up a small or medium bag. Sometimes, I fill the bag with things for the trash. Sometimes, for donations.

I try to remember to do it the same day every week, like “Trash on Tuesdays”, or “Throw it out Thursdays. “

I think there's another method that might work as well as those already suggested: "taking inventory", sorting and boxing, but just for "storage" when and if needed. I agree though that clothing, if still used doesn't need to be donated yet.

I'm in the process of going through probably several hundred books, including collections of activities that I may no longer pursue, primarily b/c of time. I'm inventorying them, boxing them and putting them away. The inventories are computerized, so I can search for them quicker than going through boxes.

They're still available (other than the magazines and books, the latter of which will be donated), but they're out of the way.

This is NOT an easy task. I'm literally traveling back through time when I find a stash of photos, or letters when I corresponded with people and military overseas (during the Gulf War) and for a moment in time I'm in another era.

There is one item I don't plan to ever get rid of; it'll be with my dying box. That's Pete Seeger's "thanks for watching my guitar", signed by the man himself when my sister and I attended a Newport folk festival. That' precious to me.

On another issue: estate jobbers: definitely not! The first time I hired someone to clean specific rooms of my father's, one worker failed to tell another worker and a lot of valuable things were thrown out. I had also been advised by a former friend to just give instructions and let the folks work, rather than work with them. Some of those items were in good conditions and could have been sold, since they were tech devices.

I would NEVER under any circumstances do that again. Too much was lost and I remember too often what a stupid mistake I made.

Good Morning,

If you want your neighbors to love you join "The Buy Nothing Project". I have recently learned of this organization that started a few years ago.

Basically, it's set up by zip codes. You go online and donate items and people in your neighborhood pick them up. No money is exchanged and bartering is not required. You get to meet people from your area and it builds community.

Basically, it's recycling and people can hold onto their $$$ since gas has gone up, utilities, chicken, etc.

The older you get you don't as much stuff as you think you do. But you need the right stuff, comfortable reading chair, good lighting, good reading glasses.

I'm sure you'll find a home for your things. Hope this helps!

I think it's a great idea.

It's probably best to just pluck things out that you no longer use/need as you see them, put them into a bag/box, and donate them as you go. That's what I do. I then dump the bag/box into the back of my car and drop it off at the ARC donation station next to Safeway when I go grocery shopping. I kill two birds with one stone that way. I bring OUT a box of stuff and bring IN a few bags of food! Also, DH won't notice things missing, or see a 'hole' in the decor that way, so it should all work out well for you.

You are wise to plan ahead w/o going too wild getting rid of everything! Suits and formal wear is useless (for our lives, too), so off it goes! :)

I started cleaning out after having to do it for Mom and MIL.

I could clean out a LOT if I didn't have DH. Just gave away some LPs but they were mine. He won't get rid of the cassettes and VHS tapes that are 40yrs old and more. Tell him the tape deteriorates. I hate to get rid of them too but would free up so much space. BOOKS, I have handed down the children books but my husband is a History major and has a wall of bookcases full of books.

I have always cleaned out clothes. Not wearing them after a certain length of time, give away. Odds and ends of dishes, donated to a thrift shop. Sets of dishes, do you have more than you really need? That wedding china? Do u really use it and the silver. You maybe able to sell both to an antique, consignment or estate sale store. I bet there is stuff in your closets that your husband has already forgotten he has. Just box or bag up and put in your car truck when he is napping. When out, drop it off. Every so often go thru your stuff again, and that stuff you thought you could not part with now u can on second thought.

Start a room at a time or a task at a time. I did have my Moms wedding dress and my Aunts maid of honor dress. They were made of Satin and netting from 1950. I gave them to a local Theater to use in plays.

Thank you all for your thoughtful replies and tips! I will start doing this in stages. Glad that the general consensus is that stuff like this won't be missed by those who have dementia.

I'm absolutely all for recycling, but sometimes, your best friend is a dumpster. Many of these other ideas are just going to drag out the process; maybe you want it to be gradual, though,
When my dad died and we thought my mom wouldn't be coming home (COVID, before the vax; my sister and I both quarantined in their home), we rented a dumpster for the "junk." We had a garage sale last summer and will do again this summer (not all that successful) and my sister has spent a lot of time selling stuff on Facebook--none of it for very much, but she feels she's doing something.
We'll probably rent a dumpster again this summer.
Not sure what exactly we'll do with the mostly pared-down furniture that will be left when she likely goes into a nursing home within the next year. Neither of us have room for it.

Just went through this. We had already downsized, but I was amazed at the stuff we got rid of without a second thought. In your case, I would continue to get rid of stuff he would never notice. But also think about yourself, I was a big cooking type, but felt a sense of relief when the heavy appliances, pans, oodles of cooking helps went. And many things that were "still good" and "might be useful". True, but finally decided that a thrift store could arrange for those contingencies for someone else. You seem to be off to a good start. Someone said to say to yourself "I got MY use out of it."