Up or down; you can use the 'nazi rule'..

Stand up straight. Raise your arm to a 90 degrees angle in front of you. Now raise it to 180 degrees (straight up). Now devide the room between that into 3 parts.'

About exiting the box; check the rulebook for the competition you're flying in. For instance, here in the Neterlands, the starters programme allows you to exit and enter the box, but doesn't allow you to do 'everything you please' there. If you would, for instance, use a stall-turn there, your next figure will be scored a zero. Only turns and half cuban eights are allowed. This is offcourse a local rule, not something internationally applied, just to remind you that the only thing which can tell you what is or is not allowed, is the specific rulebook for that competition.

More in general, it shouldn't be about what is or is not allowed, it should be what you should strive for. You should strive to keep line, even if your programme or competition doesn't require this. You should strive to use only legit turn around figures.

Not because your current competition requires it, but because the top level requires it, and one should strive to reach that level