Watercolor pencils are ok, as I can use them with regular cardstock. But my Tombows give bolder coloring when needed. NOTE: you do need to use a good quality of watercolor paper (I use Strathmore cold press which I purchased at Hobby Lobby) and also emboss your image.
I've never been one to jump on the Copics bandwagon. They are just way too expensive for me to justify when my pencils, Tombows, and BICS work fine for what I do.
Anyway, just thought I'd share her tutorial with you. HERE is the link again. Enjoy!