Choose your street food very carefully
This one hurts, a lot. But not all street food is created equal. Some have raw toppings, like the cilantro and onion that were sprinkled on a 50-cent taco I ate in a tiny town in rural Oaxaca. Delicious, but it cost me around $500 in medical bills and antibiotics when I got home. Watch, too, to see that the food is freshly cooked -- ideally quite hot -- and hasn’t been sitting out in a cart or in a buffet tray. If it’s hot and well-cooked, then just use your best judgement around the sanitation of the cart. Life’s all about risks and rewards, so if you've done your due diligence, might as well enjoy.
Make yourself waterproof in the shower
This one is easy to mess up, because you probably don’t realize how much water you drink in the shower. In places with iffy tap water, avoid getting any in your mouth or eyes while bathing. It’ll feel weird to clamp your mouth and eyes tightly, but as a friend who frequents Guatemala told me, “It’s worth showering in total darkness to avoid total darkness in the toilet later on.”