A pot hook is a must when it come to painting from a ladder. This little tool holds your bucket from a rung and to the outside of the ladder rail.
The pot hook (AKA "Pail Hook") shown on the ladder is a right handed design, that is it holds the bucket to the right side of the ladder. These hook are inexpensive, usually rust proof, and available in most hardware and paint stores.
Pot hooks are are usually a right a handed design (they'll hook on the right side of the ladder) or they are universal (they'll hook on either side of the ladder)
If your a southpaw and you ever see a left hand pothook for sale ...buy it, you may never find another one. However the universal hooks will work just fine