If you used paper and any form of water soluble adhesive in the composition do not pour - too much moisture (as in pouring) will make the artwork bubble and wrinkle for sure. Very light coats of varnish is likely your best bet - and I mean light. The first few coats are just to "show" the artwork the varnish. Don't spray what looks like a full coating until coats number 3 or 4. It's not quick, but you don't want to ruin your artwork by being too hasty. Just my 2c! If in doubt - do a test with the varnish on a scrap piece of artwork using similar materials.