If you don't care how nice yours look this can be a really easy trick for you but it might look sketchy. This trick can be a really nice one if you pull it down a gap and have these down pat. I will explain how to do them the nice way because the easy way looks bad and it isn't hard to learn.

Setup like you would for an Ollie and pop your tail down. Once your a bit off the ground twist your shoulders B/S and start dragging. This way you don't start your spinning on the ground and it ends up looking nice. Once you finish dragging or while you are try to get the board as high up to you as you can for a nicer style. Once you are at 90 degrees in the air start extending your legs for the impact (very important for gaps). Set your four wheels down and spread the weight out evenly over the board so you don't slip out. I find this is easier to do and especially to land when you have you stance a bit different then an Ollie. I like to keep my front foot up almost at the front truck's bolts. That way when I am in the air it is easier to keep both of my feet over top of the trucks giving the B/S 180's a nice style the looks clean and strong. 

Tip: It's a lot easier to spin if you wind your hands the opposite way you are going to spin then unwind and Ollie. That way it forces your upper-body to move along with the board and not just your feet.

Good Luck!

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