... You have to do alot of trial and error with creating textures, even with very good templates. Theres always a little distortion or warping on any kind of unwrapped non-planar object. You just have to keep making adjustments in photoshop.

the other alternative is to utilize a polygonal painting app like Blacksmith 3D or Zbrush or Hexagon or Modo, etc.

Hopefully a clothing texturing guru will step forward to offer some more succinct advice!