the easyest thing to do is keep a wide stance starting on the first part of the rail till the end of it and if you get hurt don't cry about it even the pros wreck oh and you can learn on any rails I learn on a bike rack in front of my house stay at it and you can do anything
I've got my fujatives 1 inch behind
having an inch back gives you control in pow and big mountain but you still have the easyness of spining and the pop that you have at center mount
im better at rails then jumps but i like them both there both tight if you can bust out big triks on them you can't tell me a 450 on takes balls true you need balls to throw a 1080 but rails are so much more technical then jumps are
bios are opposite of corks and are easyer then flatspins if you do a rodeo more inverted then its a misty witch isn't as hare as a true rodeo and flatspins can be done off jumps and its still a flatspin
flatspins are harder then bios, but if you want to do a bio just throw like you'd do cork ,but you look more forward and drop you shoulders to your tips and pop like a biznach