How to do a blowout at home?

I’m trying to get more volume at my roots and tutorials say to use a round brush and a hairdryer. But my hair keeps getting stuck and tangled and I can’t do the twirling thing to get the brush out. In the end I have to pull it out and loose a couple of strands.

What am I doing wrong?

I’m trying on day old dry hair. I’m afraid to try it again, but will trying it on semi dry hair make it better?