Two things you might try- for your appliques, try fusible web. It is sticky on one side but not the other. Trace your design on the smooth side, put the bumpy side next to the right side of your fabric. stitch on your lines. Cut a small slit in the web and turn the applique, right side up, now the bumpy side should be outside on the back. At this point you can press to your background fabric, or to reduce bulk, trim out the inside webbing. Press and stitch by hand or machine. Hope that makes sense. As for the ruler, glue a small square of fine grit sand paper to each corner. It will help 'grab' the fabric and not slip. Hope this helps.