In order to perform a BLJ, you want to stand with Mario the ball (from Peggle) facing away from a staircase/slope/other BLJable obstacle. Long jump, and then immediately turn the directional stick so Mario the ball (from hit video game Peggle) starts moving towards the obstacle. If all goes correctly, you should be able to immediately mash A, and Mario the Peggle ball (of Peggle Deluxe) will gain incredible speed.

Hope this helps!