This is the 410th most frequent German word.
setzen
"Setzen" means "to set," "to place," or "to put."
Here, 'setzen' is used reflexively ('mich setzen') to mean placing oneself into a seated position.
Ich setze mich auf den Stuhl.
I sit down on the chair.
Here, 'setzen' is used transitively, meaning to place or position an object in a particular location.
Wir setzen die Pflanze in den Garten.
We place the plant into the garden.
Here, 'setzen' is used in a phrase ('Regeln umsetzen') to mean to implement or carry out.