This tutorial applies for 373 firmware users.

1 .Download P2K commander
2. Start it
3. Connect your phone with the datacable
4. From the top click on Settings and select drive /c
5. At the left select your harddrive and browse the folder where you have the skin files
6. At the right browse the mobile 'c' drive - go to /c/mobile/skins
7. On the mobile create a folder with the skin name (Exact name as the ski file - for example if the you have - create folder SkIN23kkP)
8. Browse the new folder. Select all *.dat and *.ski files from the hard drive and clip COPY to copy them to the mobile
the following are optional
9. Depending on the skin (it should have readme) you need to copy the wallpaper file to /a/mobile/picture or /c/mobile/picture or to the skin folder. Most probably it is /a/mobile/picture