when you come to the end of a turn, you feather the pistol grips
don't brake, just mid way.
this will cause the drive belts to slip.
then feather to a forward turn slightly
feather to neutral again, pull back wards toward you and away from the turn, then feather back into the turn.
this will make a three point turn with a belt drive walk behind when done correctly.
Unless you have a tbar, then there is no feathering, just pull back on the red stationary bar on the corner where you want to make the turn.
this causes a tight three point.
T bar belt drive is amazing for this, once you learn how to do it right.