Honestly, the vast majority of males are only concerned about their own reason for being there; they are not typically on a situational awareness level to concern themselves with the bathroom habits of other men. That is just not something many of them are into. It's a breach of the assumed male etiquette, actually.
So that out of the way... one thing I do is to flush while I'm handling my business (hey you know, the anatomy makes a different sound and that takes care of that problem 100%) and that's a very common practice for most men (even women) who are "pee-shy". And there are many reasons why cis guys sit to pee (or uh... other purposes) and it is absolutely not uncommon enough to draw untoward attention in and of itself. Not every cis guy has a python or a correctly placed urethra come to that (those unfortunate guys have to sit too). Otherwise, they just prefer to or they're just used to it, or they're insecure about their size or whatever the hell else it is. There are very many reasons why they also sit. 98% really don't care. I'm leaving 2% for the perverts... those would be the only ones who'd be snooping for the feet placement and such.
Now, the line of sight rule... the most important. You take a sweep of your eyes to get the lay of the land, lock onto the target and go straight there. If there's a wait, you fix your attention on anything other than the other guys in there. Anything else, ceiling, floor, walls, graffiti, sink fixtures, whatever. It's just the common courtesy. Avoid direct eye contact, no staring and absolutely no peeking at junk (although I'm sure that's common-knowledge, still good to mention it anyway).
Talking? That is not strictly a rule, but is a strong suggestion. In example, if you're directly addressed and you say nothing, you can be read as an ->-bleeped-<- or your silence could also be read as hostility and either can present a problem you don't want. Or you know, sometimes you get asked to pass a roll or something. So in those circumstances it's appropriate. Otherwise, silence is golden.
I'd wish you good luck but you really won't need that. I'd been using the men's well prior to T and never had a problem (even packed in there like sardines once and with a lot of bull->-bleeped-<-ting going on all around; perfectly fine). Just act casual and try not to exude nervousness. You'll be fine.
