Teching a ground attack

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What are good ways to practice teching a ground attack. Since I find that sentence confusing, I'll clarify by saying, a similar example would be to practice ledge teching by placing motion sensing mines on a ledge, Up B-ing into them and then Ledge teching, but occasionally I will see a player get hit by an attack, and I think, DI/SDI into the ground and tech it. I think Leffen posted a way to practice this, but I'm not sure. Also, I only have one controller, so what I have been trying to do is use motion sensing mines, but that doesn't really work.