How to get a transport card
You have to get a transport card that you pay every month or once a year. This card is called "la carte Navigo". You get it by going to one of the big stations in Paris like Nation or Châtelet where they have a big customer center. You might have to bring you RIB. You need to know which "zones" you will have to use while you are staying. The zones are divided, begininning from the center of Paris - zone 1. The farther away that you come from Paris, the higher the number will be. The numbers go from 1 to 5. At the office they will make a plastic card with your picture and name on it. It's free to make the card.
You have to bring your small plastic card to one of the automats to activate (and pay) it. Here you can choose the options in English. Most people buy one month. Think of keeping your receipt, because your employeur might refund you some of the money.
You can read more about the transport here.
Bicycles for rental - Velib'
In Paris and the cities autour, you can rend a bicycle, either with your carte navigo or your credit card. You choose your bike, you go where you want, and then you leave it at one of the Velib' places.
There are different prices and many places to rent the bikes. You can read more about the Velib' on the official site.
