I dont know if there is an easy way to do that. I have gotten the "feel" of it over time, and dont think about it now. Maybe marking it out and putting cones on the other side of the runway would be an easy way if you can't paint box lines at your field. Or mark it off and see if you can find references with trees or something. I wouldnt worry about the 60 degree vertical box. You have to be right on top of you to get anywhere near that. It is a lot higher than you think. I don't think it really gets enforced at all unless you end up right on top of yourself. If you are flying at ~150m in front of you which is the ideal place to be, getting to 60 degrees vertically in sportsman is nearly impossible.

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