A few suggestions to make your stay easier and more comfortable.
Regardless of the season and the area your are visiting, it is advisable to carry warm clothes, loose trousers, cotton tops, hiking footwear, good sunblock and a hat (to protect you from the sun and the cold).
Don't let your personal belongings out of your sight.
Avoid using unofficial or unmarked taxis during the night.
Avoid exchanging currency in the street or carrying large sums of money. Use exchange bureaus.
In case of altitude sickness, rest well during the first few days and avoid physical strain; drink mate with coca leaves or take coca tablets.
Drink plenty of fluids, particularly in high altitude zones, using only bottled or previously treated water.
Purchase your food at restaurants and avoid street stalls.
Peru's electricity runs on 220 volts and 60 hertz (except Arequipa where it is 50 hertz).
There is no set percentage for tips, it depends on the customer's level of satisfaction with the service. 10% of the bill is usually considered adequate.