My collage work is arranged and composed before I use a drop of glue. First, I paint paper for the image, using acrylic paints in a variety of paint applications from very thin and transparent to layered textural surfaces.
To avoid buckling and curling of the collage, I start by taping all four edges of the support paper securely to a board. I use artist tape (like masking tape only more reversible) for smaller compositions and paper tape (the kind you wet, used to seal boxes) for larger works.