Slice the watermelon that you want to use, you will need quite a lot.
The easiest way to slice it is by cutting vertically like here and then horizontally to get the pieces off.
You can save the rest of the watermelon.
Put it in a bowl, and if it has lots of seeds you can remove them. This one was almost seedless.
Mix with feta cheese - as much as you like.
Slice the onion in rings.
And add to the salad.
Sprinkle with basil. You can also use fresh basil, but unfortunately I didn't have any.
Mix a bit of oil and thyme in a cup and pour it over the salad. It should only be very little. You can add a bit honey to the oil too.
Mix it well and it's ready! Sprinkle some extra basil on top, for it to look nice.