Download skin..
Example
i download --> p_m4a1 v_m4a1 w_m4a1
than go to : Cs Folder --> ( programms, programm files )
-> cstrike -> Models and than just copy the file
where you downloadet and the old will be deleted..
or you save the orginal on desktop or in my data
than start cs.. and if you dont like the skin
do it like you do with the dowloaded file..