It helps to move the toy around (i.e. don't leave it on one spot too long).
Also, vary pressure you personally are using on it, and vary technique (move it around in circles as you push it hard into you, move it down across you lightly, etc) so as to avoid becoming numb. My first time using it I was given that advice and so far it's worked. It took like 30 min before I started "becoming numb..." Idk, I personally didn't think I was numb but who I was doing it with said I was becoming it
Also if you get the power box control thing with it you can vary its speed, so as to avoid getting numb fast on plain high. I personally like starting slow then moving up in speed, and sometimes taking breaks in between both because I'm like, "Omg so amazing I have to stop to like breathe" and other times because I worry about becoming numb.
Sometimes it feels a little hot/ burn-y, but it's a sensation I like.
I feel like using it with lube helps prevent hurting in a bad way