Gigglespots make a great mobile to hang over your baby's crib or changing table. We use one of these photo mobiles from Amazon and just clip on your spots.
Peel and stick Velcro is not a good option in many situations. For irregular shapes and locations you'd like to stick your Gigglespots, Velcro strapping can come in handy. The straps are intended for cable and wire management but they work perfectly to create a stickable strip on a stroller, carseat, highchair, and many more places. You can pick them up from Amazon or just about any household goods store. Make sure you get the ones with the fuzzy exterior.
Each Gigglespot comes with a 1/2" Velcro (Hook and Loop) fastener on the back. We've made this fastener the "hook" side so it will stick to as many surfaces as possible. Each set of Gigglespots comes with 12" of "loop-side" self-adhesive tape to get you started. If you'd like to order more of the self-adhesive velcro tape, click this link to Amazon for a ton of suggestions.
Keep in mind that you only need the "loop" side of the tape to hang your Gigglespots but it's tricky to find loop-only velcro unless you order a larger quantity.