The nollie flip technique combines those of a nollie and a kickflip. It can help to visualise the nollie flip as a switchstance fakie flip whilst you are learning, as this can help with the timing. There are plenty of other switchstance flip tricks out there, but the nollie flip and nollie heelflip are so distinct because they are the building blocks of most other switchstance flip tricks. Concentrate on popping the nollie and then flipping, as this is the way to do this trick with power.