How to clean a silicone case?

I got an ipod silicone case about 8 months ago, and it's pretty good for keeping scratches off my ipod. The problem is, it seems to have picked up some coloring from the inside of my purse; the corners of the case are dyed brown. It makes it look dirty...

I have a phone which I bought a silicone case for. I was wondering is there any way I can shrink the case to make it fit tighter?

I have a pen mark on my silicone phone case and I was wondering how I can get it off. I have tried hairspray and windex already. Please help!

Im not very good at explain this, so I wouldn't be surprised if anybody didn't know what im going on about. Lets say I wanted to put a shell into a plastic/silicone casing (which would be solid) I know you have to mix a few solutions together to make...

You know how plastic, silicon and rubber which start out clear/white start to yellow over time? How do you reverse that? Is there anything I can buy to treat them to make it white again?

ive seen people like put beads and stuff on there ipods and like gems and bedazzle it to look like the expensive ones can you do it with a rubbery silicone case or does it have to be a hard shell case?? picture http://www.google.com/imgres?q=ipod+4th...