Create my own textures

How can I create my own textures for use with texture filter?

Mike,
The "textures" you load for use with the Texturizer Filter simply have to be Photoshop files. You can use photos or anything. If you want to create a good tiling texture however, you'll need to create whatever texture you want in a small file, then make sure the edges will tile seamlessly by using the Offset Filter to view how your texture's edges meet up. You can see your texture tile by defining it as a Pattern, and filling a larger file with that Pattern. The creation of a good tiling texture is explained in detail in the tutorial, Defining and Using Patterns. Use of the Texturizer Filter is dealt with in the tutorial, Instant Texture with the Texturizer Filter ,with step #4 discussing how to load your own textures.