Relax, all you have to do is take the same precautions as for any other tourist destination. Always keep a copy of your identity documents with you and keep the originals in a safe place together with other valuables, in your hotel safe. Watch out for bag snatchers and don't carry large sums of money.
Keep objects of value hidden and keep an eye on your handbag and luggage. Do not change money in the street. You should use taxi companies – call a cab by telephone or using a mobile app–. Ask for advice at your hotel.