For this Tutorial you will need:
Photoshop (Or any kind of paint(not windows paint))
Half Life Model Viewer DOWNLOADLINK
Counterstrike 1.6
Okay Let's Begin:
1st Step: Open HLMV. Choose Which model you want and Export the texture you want to edit. Open the .Bmp in Photoshop. See 1st picture!
2nd Step: Change the .Bmp into RGB mode so you can use it later. See 2nd picture!
3rd Step: Open the texture that you want to reskin your model with. Im going to use Camo By: G-Flow (Can be found on the Free Camo Thread :) ) . See 3rd picture!
4th Step: Select The Clone Stamp Tool and set the Opacity to 30% to avoid erasing detail. See 4th picture!
5th Step: Make the Camo texture your current viewing picture and go to the bottom right corner, then alt-click it to select it as your starting point. If you recieve an error make sure your pictures are in RGB format. See 5th picture!
6th Step: Now Start brushing! Be careful not to click on every spot because this will saturate the area with more pattern then it will if you maintain a smooth stroke. See 6th picture!
7th Step: This was only one texture, now you have to do this to the other textures. Your texture should look like this: Free Image Hosting At site
Remember to go to Image/Colormode(or whatever has the indexed, adn RGB stuff) and select Indexed otherwise the texture will not work!
Hope this help's!