First, if the person made it easy on you the skin should have a few folders, materials, sounds, and models, and possibly a readme.txt or credits.txt or something.
If the skin pack is like this, then good this will be simple. Either,
A) CTRL + left click all of those folders (materials etc.) and drag them to a folder, then cut them to your cstrike folder.
B) Extract them to your cstrike folder (RAR people only)
C)Save the .rar or .zip to your desktop and extract contents to Cstrike.
There are many combinations but those are the best.
If you did this part right, it should say something like, such and such already contains (folder) would you like to overwrite it? Click YES TO ALL.
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This could also happen.
The person only gave you the .vtf or .vmt or w/e, in short, actual skin.
Then you have to go on a hunt in your cstrike folder or make folders of your own.
Lets say i have eq_flashbang skin, just that part.
I would goto my materials, models, grenades, and all of that until i found the eq_flashbang place.
This is hard and these types of skins usually come with a readme. You must go on a hunt otherwise.
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The skin IS your cstrike folder.
You could either extract that your your Counter-Strike Source folder, or extract the cstrike contents to you original cstrike folder.
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