Technically, that is a front wheel lift. A rear wheel lift is a completely different move.
1. Get out of the saddle, neutral position. Don't be sitting.
2. Compress the fork, and at the same time you shift your hips back, pressuring through the legs and pedals.
3. It's the sudden shift of the weight/center of gravity back, combined with the release of the compression, that brings your front wheel up.
This is the position to practice from. Practice shifting your hips back and forth. Then, move them back and pressure the pedals. Then, add the compression. It's best to pedal some, slowly, and then coast, tyring the lift, and then pedal some more, coast, etc. Foam noodles are really good to practice: very forgiving.
