So, to do a switch lincoln, just go off the jump backwards and instead of doing nothing, do a lincoln?
Brilliant! I never thought it could be that easy.
Seriously though, I tried a bunch of them at the water ramps and they're super hard because you're looking over your shoulder to spot the takeoff, then you have to spin your head back upright, then set the lincoln. Of course, I look over my left shoulder but throw a lincoln to the right, which makes it harder.