Complete your painted artwork, allow to dry
Remove frame backing and glass.
Measure and mark placement of cabinet pulls on back of frame.
Drill holes through frame and attach pulls with screws (you may have to use shorter screws than those that come with the pulls).
Re-assemble frame, inserting picture behind glass. To make the tray more water tight, add a thin line of clear caulk where the glass meets the frame.
Tie hemp cord on cabinet pull, adding charms if desired.