compress the tire?

i just dont understand compress the tire, it seems simply but it confuses me, like how do i do it, if you think your answer is too basic to this then please post it and if your think your answer is to complex for this then please post it and if you dont have an answer then please post it.
thanks to anyone who responds

well there are two ways, with and without prehop. first without. basically it’s pushing your weight down to squish the tire before you jump, this will give you more spring to your hop. think about it like this: stand straight up)not on the uni, just your feet), now jump in the air. what’d you do? bent your knees, the straightened them and pushed with your toes. same thing on a uni, you push down with your weight and compress the tire to get more spring. to do it with a prehop, you simply leave the ground a tiny bit then force the uni into the ground compressing the tire a whole lot, then going for your bigger jump.

Think about jumping on to a big spring, and then bouncing off really high, that’s all there is to it, the spring will compress when you jump on it, and your tyre acts very much like a big spring.