Step 1: Go get stuff.
- liquid latex (get Clear #10)
- fabric (canvas is ideal since it is strong, tightly woven and doesn't stretch)
- a bar of Dove soap or similar ( bacon soap is tempting but not recommended)
- three plastic dishes (large enough to hold soap)
- baby powder
- 1 cheap paintbrush
- paper towels
Step 2: Prepare the materials.
Step 3: Paint your first coat.
Now dip the bristles of the brush into the liquid latex about halfway. Rub off the extra latex on the side of the container so that it doesn't drip everywhere.
Quickly paint a thin horizontal layer of latex onto the canvas. By horizontal I mean that all brush strokes should be made horizontally across the surface of the canvas.
The first coat will take longer and use more latex than all subsequent coats.
Step 4: Paint the second coat.
At this point you are going to want to lay down the second coat. This time make all your strokes vertically or, rather, in the opposite direction of your initial strokes.
After the second coat your fabric should be airtight.