Just lay out the mozzarella, tomatoes and basil leaves in layers. Like in the picture. Gammy always has basil growing in a pot out on the deck or inside on a windowsill in the colder months. If there isn't any fresh basil leaves available just use the dry stuff and sprinkle it on after everything else. Sometimes I stray from the straight and narrow (would you believe it?) and instead of basil I smear some pesto all over it. And or use arugula leaves instead of basil.
The quality and the degree of ripeness of the tomatoes is real important. We use Roma tomatoes that aren't too firm and not beginning to get too soft. No green around the stem spot and no hickeys on the skin.
There are lots of different ways to go with this simple but real good and basic Italian salad. Sometimes we put slices of avocado in with the cheese, tomatoes, and basil. Boy, that's good. You're the chef so let your adventurous side out and tweak it the way youwant.