Long experience was my teacher. When I knew I would be hunting I did tend to wear basic muted solid colors, nothing flashy, reflective or too dark, in whatever fabrics fit the weather expected. But for me pretty much whatever I was wearing always worked just fine too in a pinch. For pants, I easily wore far more Levi's than everything else combined, even in the dead of winter snow country. I don't believe in the need for camo for hunting (or fishing - give me a break), but I guess they are great for parties and shopping mall excursions, and when the "game" is man. Didn't wear camo for bow hunting or over 50 years of predator hunting. Bought some once for some foolish reason, but never wore them. If your spot and stock and calling skills are good you simply don't need it, or anything else special for that matter IMO.
YMMV naturally, and that's fine. Whatever gives you confidence and helps you be a better hunter can't be called wrong.