"I put my hat on my head."
Translation:Ik zet mijn hoed op mijn hoofd.
Because the English "putting on" (in the sense of wearing/putting on a hat/beanie/crown/...) translates to the Dutch compound verb "opzetten" (which has multiple meanings btw, like setting up a tent or stuffing dead animals =)). You can lay something on your head, e.g. when measuring the length of a child against the wall you could say "Ik leg (without the "t" for first person) een boek op mijn/zijn/haar hoofd" but then you're not "wearing" the item.
To be honest, I think the English sentence is a bit weird... "I put my hat on/I put on my hat..." would suffice imo because without any extra information it's only logical you would put it on your own head
Hope this helps =)