I've had many successful stencil project on light colored shirts, I always use the freezer paper technique.
My problem is when I stencil on dark colored shirts. I've only had this problem with t-shirt fabric, I've been successful on quilters cotton.
The paint seems to seep into the fabric so much more. I end up putting on so many layers the image is blotchy, super stiff and well yucky looking. I've tried waiting for the paint dry between applications this has lead to bleeding where the stencil pulls up after a use or two.
I've seen awesome projects here so I know I'm doing something wrong but I can't figure out what it is.