You cannot really make level because it needs too much knowledge but you can help me with 2 things:
Give some level ideas
Just post in the "Level Ideas" forum your idea. It can be a text or, better, a text + an image you made with paint or whatever. It's always easier to explain a level with a draw.
A module is *one* 3d objects. A level is made of different module. For example, the ramp is a module, the target 300 is a module, the box is a module.
If you have some idea of module, you can create them with 3dsmax or blender (with a good exporter plugins).
When creating a level, I can take a module, scale it, change its color and rotation. For example, to do a pyramid, I can use the box module, so you don't have to create a pyramid module.