Well, it's simple. Here is how you do it ( via Aleh, from Sortitoutsi ):

1. Extract the zip/rar file into;

Club Kits go here:

My Documents/Sports Interactive/Football Manager 2008/Graphics/Pictures/Kits/Clubs

You may need to create the folders above, if they do not exist.

International Kits go here:

My Documents/Sports Interactive/Football Manager 2008/Graphics/Pictures/Kits/Nations

Default Kits go here:

My Documents/Sports Interactive/Football Manager 2008/Graphics/Pictures/Kits/Default

2. You may need create the above folders, if they do not exist.

3. Load up FM, go to Options > Preferences > Display and Sound

4. Untick ''Use skin cache'' box

5. Tick ''Always reload on confirm''

6. Then click ''Confirm''

7. Then finally restart FM.

8. Now the kits should work without problems.

they will appear only in the "information" panel not match screen, am i right?

Normally, the kits should appear on both screens. But SI made some modification there and i'm not sure if they appear on match screen.