This is a very impresive trick that's not all that hard.I first started doing them off dirt table tops that weren't very big about 3 feet.It doesn't mater what you do it off as long as you can clear the gap if it's doubles.You should make shure you can pinch the seat because you take your arms off when you do a barspin. as long as you can get the bars around with out them hiting your body they should go around easily (having a gyro helps because then you don't have to unwind your bars after the jump). You want to hit the jump at a medium speed and go off ,tuck, pinch your seat, throw your bars with one hand, and let them come around, and catch them and land clean.Roll away stocked and next time go for a suisied barspun
If you plan to dirt jump this trick is a must.All you need to do is go off the jump and crose your bars so your arms overlap making an X .The only thing is you got to get at least 2 seconds in the air because it will take you that long to cross and uncross your bars.
If you can not do this you should quite BMX and take up something like chess.all you do is go off a jump and turn your bike on its side to one side.
You do this by turning you bike on its right side (while in the air )and your bars to the left or your bike to the left and your bars to the right .