MicroLifts

You could call the Solemate™ MicroLifts™ the world's smallest orthotics because they really change the way you stand and walk. Initially developed for open toe shoes and high heel shoes, our customers stick them to their feet, in their sandals or on flip-flops. The adhesive is medical grade, like band aids, and the peel-off adhesive protective layer removes easily. Full instructions are in the package. Not recommended for attaching to the feet if you are diabetic and have an increased chance of ulceration because the glue sticks really well. Testing of the adhesive demonstrated that the typical person can expect on average three uses from a single pair based on removing them and sticking them back the next day. You can also just leave them on. 
Great for bare feet and shoes.