If self-adhesive strips are a little too aggressive for your painted surfaces, you can always use a strip of felt pinned in place to hold your Gigglespots. Another trick involves sticking a piece of Drafting tape to your wall before sticking the adhesive strip. This reduces the agression of the adhesive that comes in contact with the walls. On some walls and painted surfaces, even Drafting tape can be strong enough to pull paint off so be careful and test in an inconspicuous area first.
Painter's tape is also an option but can be more aggressive than Drafting tape, and only comes in blue. Even painter's tape can pull paint off walls if left on for more than 24 hours.