Chop the tomatoes, cucumber, bell peppers, and red onion.
Stir the vegetables in a large bowl, then add in the salt, olive oil, and crumbled feta. You don't want to mix it around too much. Over mixing will make cause the tomatoes to give out too many juices. Serve chilled.
Chop everything to a similar size- So that each bite has a little of everything and no ingredient overpowers another, chop or julienne the vegetables to a uniform size.
Take out the tomato seeds- When you slice your tomato in half, scoop out the seeds and leave them out of the salad entirely. This will avoid their sliminess from ruining the texture of your dish.
Add the tomatoes at the end- The less you mix them around, the fewer juices they will give off. Leaving them until last and mixing gently will help you avoid a soggy salad.
Add the dressing last- Because the salt will draw out the water in the vegetables, add the oil, feta, salt, and pepper at the end to avoid leeching moisture from the salad before serving.