I wrote an article on my blog about how to make street art stickers using ordinary printer paper you get at office supply stores. You don't always need to buy blank adhesive labels or re-purpose some pre-printed shipper's labels. By making and applying a simple glue, you can come up with the adhesive similar to what is on the back of postage stamps that is dry to the touch and bonds once you apply moisture.
I'll try out different weights of paper but the standard 20 pound bond I had on hand seemed to work well enough for the first test run hand drawn and painted stickers. The one drawback I'll call out about using light bond paper is that inks/paints tend to bleed easily. I am also experimenting with applying acrylic varnish to the illustrated side of the sticker to provide some durability.