Silly question lol...about shuffling

Hey everyone, I've been noticing in a lot of the videos I watch that the Sybil will hand shuffle the cards extremely fast, and it almost looks like they are pulling cards from the center and slamming them back down very quickly. They go so fast I can't even tell how they are shuffling, but honestly as stupid as it sounds it looks cool and I want to do it but I just can't figure it out. Got any tips?

You may be able to find interesting methods on Youtube but not necessary.

Tip: Shuffle the way you want and then practice until you get REALLY FAST.

I always thought I was a lousy card shuffler till I started using the Vintage Lenormand by tarotbyseven. Good card stock makes all the difference.