360s: Practice, that’s all there is to it. You have to do the motion fairly fast to not jump, and you only have to do a 245 degree motion (I do 270 because BB requires 270 and I like to try and keep the motions in both games as close as possible).
720s: Don’t even try them until you can accurately do the 360 motion. Once you can consistently 360, start doing 720s by jumping and doing the motion in the air. Again, you only have to do a full 360 + a 245 degree motion (and again I do 270), so 605 degrees lol, or 630 depending on which way you’d like to do it. You can eventually learn to do it on the ground but really the only way to do it standing is to buffer it in a jab/short (you can actually do a walking 720 this way, start and end the first 360 on forward, then when you’re ready to finish it do the other 360, but you can’t let go of forward before doing the other 360 or you lose it). It’s possible to do a standing 720 WITHOUT buffering in a normal, but it’s like physically impossible I’ve only heard of one person who can do it.