Stick with black cotton fullbacks/bikinis/hipsters. Discolored is awesome, but most get 'weird' about it. I prefer you to use old pairs, preferably ones you dont like, don't wear, don't fit right etc.. holes, rips I am picky with style and color etc. No White (light colors), NO Lace, No Mesh, No Sheer, nothing 'Frilly', no white gussets.
I am also fond of dark colors like Purple, Blue, Red, Orange, Maroon, Teal, Turquoise. Also have a thing for Neons, stripes, polka dots.. nerdy panties. I never want 'ass' smell! there are reasons these are tailored in such a way to avoid contact near the butt.
if you have a pair you'd like my feedback about, upload it below . You can also use the 'Grid' method, by layin all the panties out on the bed and snap a photo