Picture of Picatinny Rail Covers
This is an easy way to make comfortable, durable, and low profile rail covers for accessory rails. Not only are they dirt cheap to make, but they're easy to cut to size. Note that they're one use. Once you take them off, they're pretty useless, but it's not hard to make more.

Step 1: Materials

Picture of Materials
You will need: Duct tape of your choice, HVAC tape (adhesive aluminum), Straightedge, Scissors, Razor knife.