I recently watched (again) a video by Jane Davies in which she adds more paint to partially decorated collage papers (papers she used for lifting paint when working on other pieces). She then arranges some of her decorated papers under a pre-cut mat (hers was 4×4) to find pleasing designs & create small collage pieces. You can find the video here. And do watch others of her videos. I am a fan of her work and her techniques, which she generously shares on her blog. Here are the ones I made, using a 6×6 mat. Although the papers kept sliding around under the mat, I persevered and was happy with the results.