What is best way to hang metal trays on the wall?

Try using a few cup hooks to support the trays..

I like Command strips. It might take 2-3 for heavier trays, but the strips are strong and removable. 😇

clothes hanger bent...leave the on the rack hook intact to hang it from the wall. Bend the 2 sides so a upward so a resting place for the tray is made.

Requires bending wire coat hooks.. leave the hange part intact. See if you can schrunch The wire on the right and left ends top to bottom.... basically narrowing the part you would shove in the sleeve. The bend the narrowed point up ward to hold the tray. Bend it howere much is needed to hod the tray secure. If you want you can close the loop of the made from hanger hook.

Just in case you are looking for a hanger for the tray and not the wall, Flatiron makes a sizable disc hanger, it may take two for a large tray. Hope this helps.

i second the command strips! I live in england where the walls are totally different than the us and nails falls right out! I use command strips for EVERYTHING!!!!