In reply to GeorgT:
I had a similar issue, constrained by the rafters in my garage for height. I built a free-standing wall with a 30 degree angle. The board length was 8ft, with an approximate 8 inch kicker.
I use a splatter-style setting, you have to be a little creative with your blocs depending on what you are trying to train for. Loop traverses for endurance, straight-up 2 move power problems, diagonals for some longer options. I tend to have small screw-on or minimal friction foot-holds to add some difficulty and keep the footwork honest.
My wall is based on this guy's video. I found it to be the most insightful YouTube video out there, covering the build, materials and tools.
Another good source was Power Company Climbing , they are doing a homeboard series covering things like kicker size, angle, hold types
Hope this helps, good luck on your build.
Jim