This tutorial will show you how to take a spray from this site, then edit it to add your own text. It will cover conversion from the .vtf file format to .tga, so you can open it in Photoshop or Paint Shop Pro. You will also be told how to convert the edited .tga back to a .vtf.

Go ahead and download the spray that you want to customize. I'll choose the first War of the Worlds spray since it has room for some custom text.

You will notice there are 3 files in the .zip:

installation.TXT
waroftheworlds001.VTF
and waroftheworlds001.VMT

Extract all 3, then delete the installation.TXT.

Now we need to convert the .VTF file into a .TGA. To do this we need a program called VTFTool.

Download VTFTool by clicking here

Place the VTFTool.exe into your _USERNAME_\sourcesdk\bin folder, then open it.

Choose File > Convert to TGA > File... then select the waroftheworlds001.VTF file from where you extracted it to. Set the "Material source files" and the "Compiled material files" locations to your desktop then press "Let's go".
This should've placed a .TGA file and a .TXT file onto your desktop, delete the .TXT file.

You can now use your favourite image editing program to open the waroftheworlds001.TGA and add your own text.

When your done editing, simply save over the .TGA file.

Simply use VTFTool again to convert the .TGA back into a .VTF.

File > Convert to VTF > File...

If there's already a waroftheworlds001.VTF in the output folder (e.g. desktop) then delete it before pressing "Let's go".

So you should have a file named waroftheworlds001.VTF after converting from the .TGA.

Find the waroftheworlds001.VMT file that you extracted at the beginning and put it next to the .VTF you just made.

Put both these files in the materials\VGUI\logos folder of the specific game you want them to show up in.