Didn't see one of these, so I decided to upload one I made for another forum a while ago. Maybe I'll upload one on how to make blended textures/transparent textures and animated textures later, don't know yet.
To create custom textures you will require VTFEdit.
To get this, just type VTFedit in google, and click the very first link. Download it. While installing this, near the very end it will ask what you want it to associate with. MAKE SURE YOU ALLOW BOTH. VTFEdit 1.25 Graphics Tool Download, Half-Life 2 miscellaneous Nems tools is down. Download it here.
The first thing you do is get your texture: Here is mine.
Now open VTFedit and press CTRL+I. Find your picture. Make sure the picture is Jpeg.
When VTF options pops up, leave everything as it is and click okay.
Done! The picture is open. It doesn't matter how large or small the texture is, it will still work.
Now follow me over to C:\Program Files\Steam\steamapps\USERNAME\counter-strike source\cstrike\materials
In this folder create a new folder called 'mytextures'
Now lets head back to VTFedit and start our work.
Go to file and Save As. Once here, make the name "custom_name" or something that is not used by valve textures so you can find it easily in hammer such as "wow_texture".
MAKE SURE YOU SAVE IT IN C:\Program Files\Steam\steamapps\USERNAME\counter-strike source\cstrike\materials\mytextures OR IT WILL BE CORRUPT!
Once you have finished that, go back to VTFedit and select tools and click 'Create VMT file'
Skip to options and select Surface1 to sound like how the surface would sound. I select concrete because I am using a concrete texture. If it is glass, you would click glass and check Translucent.
You are done! Did it work?!
OF COURSE IT DID!
Keep in mind, these are flat textures, not blended ones. I'm no good with blending textures, takes a lot of time.
NOW! For this map to work for other players, you must Pakrat the textures into the Bsp.
First, download Pakrat. Gamefront
Compile your map, and place the .bsp on your desktop.
Open up Packrat.jar and select your map.bsp
Once that is done. Select add, and search for 'mytextures'
Once there, CTRL+click all the textures you used. Their VMTs and VTFs.
Once that is done, go to file, save as BSP. AND YOU ARE DONE!