Any ideas for how to teach a subordinate E-5 tact?

SSG Matthew Kreisz I hope all turns out well for you and your E-5 promotable Soldier as well.

I would be brutally honest and tell him that if he doesn't change, his chances for advancement are very slim at best. Ideally, you can provide him of some examples where he could have handled a situation better. But, don't sugar coat it. Remember, you are doing this for his benefit and to better serve those both above and below him. His is setting a bad example for those he is responsible for. When I was awarded my MSM, one of the attributes noted was my "application of tact and diplomacy to insure the smooth functioning of his organization"

I'm a natural at tactfulness. In all seriousness, all he needs to do is work on his tone to make it sound more neutral. Also, don't forget to place a slight giggle within your questions/responses when addressing a superior/peer/subordinate, etc; with something that normally would piss you off. And ALWAYS, ALWAYS follow with Sir or Ma'am. I hope this makes sense, as it has never gotten me trouble. Also, Youtube University helps.

Be the example first.

He should have learned tact before becoming a NCO. Verbally counsel him then if that doesn't work ,4856 Him with what is expect of him and his conduct.