Tip #1: If concerned about little bugs in the lettuce, especially if you grow your own, soak the salad in salted water then rinse well. The salt will kill the bugs.
Tip #2: I often put the olive oil and vinegar on the table so people can add extra if they want it to suit their tastes. In some cases, I don't even use the vinegar.
Tip #3: I noticed in Europe many people eat their salads "after" the main dish. I tend to do this myself because the salad helps my stomach digest the food better.