There are turnstiles at the entrances and exits of stations. Enter to the left of the green arrow. You will need to put the ticket into the slot and go through.
Do NOT pull the ticket out until you have started going through the turnstile or you won’t be able to get through. Remember to remove your ticket as you go through it – you must carry that ticket with you at all times. If you don’t have it and a ticket inspector stops you, you may be asked to leave the train or even receive a fine.
Important: If you’re travelling with luggage and there isn’t a special wider gate/turnstile, we recommend you push the luggage through ahead of you, THEN go through and take your ticket, otherwise you will get stuck!
When you exit the Metro, you do not need to do anything with your ticket; when you leave an RER station, you will need to put it through a ticket turnstile again.