In Chile the standard tip in a restaurant is 10% which is sometimes added onto the bill but more often than not you need to leave behind on the table. If paying by credit card you can ask to add the tip to the bill and indicate the standard 10%.
Do not tip taxis.
If you drive a car in Chile, in particular Santiago then there are places where you can park for free but there may be a man or woman "helping" you to park. This person works for tips. They can wash your car while you are away usually also. The tip you pay them should be anything from 200 pesos or more depending on the length of time you stay. I usually pay around 500 pesos.
In supermarkets the people who pack your bags only work for tips. They are not paid by the supermarket. Depending on the amount of groceries you could tip anything from 50 cents up to around 500 pesos. The 10% rule is not hard and fast here, just whatever loose change you have.
It was very nice to notice that people in Chile don't really care much about what you're wearing at the beach (well, if they do, they are very discreet), so it was nice, you feel more relaxed to realize that. After all, you are at the beach!
Anyway, guys generally wear bermudas instead of speedos and girls wear either one piece (maïot) or two pieces (bikini). If you decide to wear speedos, it's ok. If you want to wear jeans pants and a sweater, it's ok too!