If you have`nt done so already, take a look at the sticky`d "how to`s" at the top of this forum; I have posted the lesson plan for spinning 3`s right out of the AASI handbook. There may be some tips in there that will help along with the good points already made.
Along the lines of what Sedition was getting at, another way to help work up to solid 3`s (FS or BS) is to carve into the side of the trail where there is a bit of a bank. Carve hard into a turn and pop off which ever edge is appropriate for the direction of spin. You will have carved 90 degrees of your spin before leaving the snow. This will help you to focus on the landing phase.
Another tip to make these a bit easier is "pre-winding" Basically, as you prepare to spin, counter rotate your upper body a bit and when you are ready to spin, rapidly unwind in the direction of the spin; this will give a lot of momentum to your spin as you leave the snow.
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