This is yet another XCM move called Flash Drei.
Step 1: Starting Out
start out in the sybil grip see here for detail Sybil grip
First, the grip is just like the sybil grip.
Step 2: Other Hand
Now this is a very strange grip. you need to spread index and ring finger apart as wide as the deck. then bend middle finger down at second knuckle. put around deck. have fingers around 1 packet of cards with 1'st digit of index and ring finger past the packet.
Step 3: Lift
Lift up packet with hand and one more packet with thumb.
Step 4: Twist Up
With hand lift up packet so it is on the top of your hand. Then twist up rest of packets.
Step 5: Close
Close by putting middle packet onto lower packet and then top packet onto it.
Step 6: Experiment
Now you know the basics so make something up. You can do many different cuts from this position.