Get good at backside boardslides first. Ride up to the rail like you would for a fs 50-50. Ollie up and get yout board on the rail just like for a bs boardslide except you might wan't to let your board be a little crooked (it will slide better). When you land you have to turn your head a little to see behind you. Keep your body centered like a bs boardslide. Come off by turning your legs back to regular or turn your body and legs to come out fakie. Peace.