Says it in the title..

U right click on the skin and choose save picture as...and then follow my directions.
1.After u save u go to start
2.at start u pick my computer
3.then u go to local disks
4. Then to my games
5.then to thinktanks
6.click game
7.then click data
8.then click shapes then into tanks
9.u go down and rename the original tank skin and right click and push rename and call it wutever u want
10.then u look to the left side and go to my pictures and find the skin
11.once u find the skin u right click and select cut
12.then u go back and right click anywhere but another picture
13.after u right click select paste and rename the pasted picture tank01 for a light tank,tank02 for a medium tank,tank03 for a heavy tank,and tank04 for a ufo.

THANKS :P

Np