Press the iron's tip against the circuit board's L1 solder pad for a few seconds to heat it, then feed the solder wire into the heated area until there's a small glob of solder on the pad.

Re-heat the solder while holding the inductor in its outline, so that its end caps (the sides with the notches) are resting on the circuit board's pads.

The power inductor is symmetrical and can be soldered in either orientation, as long as the notches are above the pads.

Remove the iron, then remove the tweezers once the solder has cooled.