The colors? They are just for fun. Nothing more than fashion.
Make sure you stretch the foot so that it is not too tight over your skin. So in this case when I do the bottom, I spread the toes out a bit so that the skin is taut. You do want to stretch the tape some.
Do not just rip the tape off your skin. You are supposed to slowly peel it, lifting the skin as little as possible.That is when you remove it but I'm also talking about when you apply it and it's not quite right so you peel it off to redo. (You can tell I've done that!)
Cut it with the backing on it before applying. I usually remove a piece of backing right where it should go on the heel once I've made my fork which takes a bit of practice.
Warm it up with your hands to make sure it sticks well. Basically rub it good.
It will be wet when you get out of the shower so if you put on pants and have it on your leg, your pants will get damp. Not soaked. But just keep that in mind. The bottom of your foot will also be wet so step on a towel and walk around to dry it off enough. So you can shower.
This stuff lasts probably 4-5 days. I have had it on longer and shorter. But this is average