How do I make a male client comfortable accepting my help when he refuses my help to shower?

This isn't unusual for either gender. One young CNA (male) told me that a woman in the nursing home would be so relieved to have him care for her because he was, unlike the other males, married. That seemed to make it less stressful. I'm not sure if this will work with you but if you're married you could talk about your husband enough so at least he understand that this isn't sexual.

I do know that my father-in-law hated having females give him baths or any intimate care. He allowed it but he hated it. That isn't unusual for the older generation. Modesty was important to both genders.

As long as he at least allows you to care for him you can keep working on the comfort level. He'll get used to it eventually.
Take care,
Carol

Tell him you're a trained medical professional and naked bodies to you are no big deal; they're like engine blocks to auto mechanics, or whatever metaphor you prefer.

Maybe he's modest for religious regions, or he's ashamed that his body is no longer what it used to be back when Nixon was president. Let him hold a washcloth in front of his bait and tackle, or close the curtains for privacy if he's not a fall risk,

No offense to men but most aides in a facility are women. I wonder why this gentleman is so uncomfortable having a woman help him shower.

Built trust. Give him a bed bath first. Then the next time it's his turn to shower he might feel more comfortable.

Or go to him, if he doesn't have dementia, and express to him that you understand how he feels but that you're a professional, this is your job, and that you've given hundreds of showers. Tell him that he'll feel better after a shower and it only takes a few minutes.

You leave a towel wrapped around his waist for modesty and close the curtain when he gets to that part. Watch the Teepa Snow video on youtube about bathing.

Perhaps you could stop by periodically and get acquainted with him, just chatting about "guy stuff". Don't even mention showers. Just get to know him and let him get to know you.

Maybe he'll feel more comfortable by the time shower day comes around.

tell him youve gave bathing assistance to every one from infants to harry reams -- get over himself ..

Thank you all very much for the great ways to help...appreciate it :-)

Let him keep his underwear on a few times and step away while he washes that part. Hand him clean ones around the curtain. This is very common but everyone gets used to it in the end.