Whether you're using a personal cooler to hold your lunch or a larger cooler for a family picnic, your cooler probably looks exactly like all the rest in the area. Except for small color changes, coolers can look absolutely identical. It's difficult to pick yours out of a group, and there is always the danger of someone taking the wrong one. Use some simple craft supplies and make your cooler into a personalized craft project. You'll stand out from the crowd a bit, and never be in danger of accidentally picking up the wrong cooler from the lunchroom.
Choose a theme for your cooler decoration. Covering the cooler with one theme is more pleasing than using a random assortment of decorations. The theme can be as simple as a flower garden or as complicated as family portraits, but keep your theme in mind when you are applying all of the decorations.
Use permanent markers to outline shapes and do lettering. Regular felt-tip marker ink will not stay on the plastic in cooler shells, so you have to use permanent markers.
Find vinyl stickers that go along with your theme and place them on the outside of your cooler. Regular stickers are made of paper, and will peel off your cooler surface in one season or less. Vinyl stickers, like bumper stickers, are made to withstand moisture and will stay on longer.
Cut colored duct tape into shapes or letters to apply to your cooler. Duct tape can be found in a rainbow of colors and with special effects like prism and striped looks. Push down on the tape and rub over it two or three times to securely fasten it to the pebbly surface of your cooler.