Background Design

There is a facebook group called brotips. They have there own background for their "tips" which isnt that specia, however, it is unique to their brand. I have some ideas for a new project and I need a unique background created of my own. the brotips example is just something that I saw and thought would help explain what I needed. Width: 640 height: 480 I just need the background made no wording. It is for the fitness industry if it helps with creation of ideas. Feel free to message me for any additional details. Attached is an example of brotip concept.