Easiest trick ever, try it on mellow quarters. Just pull it all the way and land it. Mellow quarters help so much. Or try footplan bri airs to get the feel for them.
Yeah like Gaston said, definetly try footplant bris first. It helps alot. When you want to go for the actual bri air its better to like whip it under you a little and just land it like a tailwhip really.