Go to a sporting/outdoor store. Ask to hold different brands/models. Narrow down your choices to the few that u like best. Then go to a shooting range and shoot/experiment with each of your favorites that u held at the store. the one that feels the best to shoot is the one that u might want to go with. Glock 26, M&P shield, ruger lc9, Springfield xd sub compact to name a few. I carry a glock 27(27 is .40 cal and 26 is 9mm but they're physically the same size) and I'm in Houston and wear the same thing as u most of the time. I'm 6ft 180lbs. My t-shirts aren't oversized at all (large "athletic fit") and I carry IWB just behind my right hip at about 4 o'clock. The only problem I have is if my shirt is too short and I bend over or raise my arms, my shirt might catch on the butt of the pistol, but printing while walking etc isn't a problem. Good luck.