LOL! Good thread.
Every once in a while I have to tell my wife that her breath smells like she’s been snacking from the kitty litter box. Humor helps to get the point across nicely.
When I was in the army there was a guy in my unit that decided he didn’t want to bathe any more. Since he was from my home town, I was elected to be the guy to tell him to shape up and bathe. He complied. The consequences of noncompliance were dire.
If you’re a provider with a smelly client, and you don’t want to be direct, you can suggest that you start your date with a shower for two.