I think I didn't make myself clear. Let me try again:
I kill a zombie wearing bandana on his face. The item is named "Bandana (Face)". I am not using debug mode and I have not spawned anything.
I wear it by clicking "Wear".
It goes on my head, becoming "Bandana (Head)".
I have to manualy right-click it and choose "Put on face" option. Then it goes on my mouth, where it should be.
If I unequip it and "Wear" it again, the process repeats.
Hope it's clearer now.