Hello. I've searched, and searched, and searched for some time now, looked through about twenty or thirty threads, and have yet to find a definitive answer.
You can turn up to 45 degrees by spending 5ft of movement.
What does it mean by turn, given that there aren't any facings?
Move 'diagonally' into a square in 'front' of you, 'turning' 45 from your last movement and:
1) spending 5ft for the turn, and 5ft for the move
2) spending 5/10ft for the turn and move together (depending on diagonal)
?
So, if you move North 5ft, and wanted to turn right without making a 90 degree turn would
Declare a turn, spend 5ft, spend 5ft to move NE, declare another turn, spend 5ft, spend 5ft to move E
or
Declare a turn, spend 5ft moving NE, declare another turn, spend 5ft moving E
Later was suggested in a thread, and might fit the whole "simplifying movement" thing that ascending and descending does by getting rid of diagonals.
This is easy enough to generalize the answer to the other movements from, so I won't ask for them (well, maybe why you would want to use 180 outside of GM saying an object will fall on you halfway through your turn if you don't move?).