You are correct dark colors do conceal a bit better, patterns like plaid or some kind of other "busy" print will help. I don't know about stripes because I'm a big guy and stripes don't work for me lol But you should be ok with a size up T-shirt and a good belt. Also check the can't of the weapon, try to run the grip of the gun with the lines of your body.What I mean is if you are tall and lean you probably don't want the grip running paralell with your belt line especially if you are using any kind of extended mag. So maybe cant the gun forward so the grip rides up your ribs. Give it a shot. Hope it works out for ya. Be safe.