I prefer the look of paper and on my Spitfire and FW 190, I overlayed paper.
This is how I did it:
1. Choose which color will be your "base" color and cover model.
2. Cut "overlay" color to shape you want. Smaller patches are better and my large areas have a "seam"
3. After first color is on, shruck, and doped... I wet patch, place on towel to remove excess water, then appy to area and secure with dope.
4. After model is finished, one more coat of dope over everything.
Hope this helps, Mitch