5 tips to avoid looking like a tourist in Paris
Don't walk with your guide and map in hand
Keep your guide in a backpack and your Paris Map in your pocket.
Only take them out when needed.
Also, asking your way is generally faster and more efficient than trying to find your way with a map.
Store your camera when you don't need it
Another thing tourists always seem to need in hand is their camera. Many of them keep it dangling around their neck or in their hand even in places where they obviousely would not need it such as the metro. Others put it on the table in restaurants or cafes.
Get a camera bag and store your camera in it when you do not need it. It will also make it more more difficult to steal.
One thing you DO want to keep always in hand if you want to look like a parisian is your smartphone. Half of the people walking the streets of Paris have one.
Don't dress like a tourist
One sure way to spot tourists in the metro is the way they dress. A group of people wearing shorts, baseball caps and flower shirts is obviousely not parisians on their way to work.
Dress a little nicer than you would generally do on holidays. The aim is to look a little more relaxed than most parisians, but not too relaxed.
For instance, you can wear comfortable walking shoes, but avoid the white athletic shoes or hiking ones.
What you can also do is study the way parisians dress on the first day of your stay, then purchase a few items to look a bit the same.
Don't get in the way
Pay attention to the flow of pedestrian and car trafic and avoid staying at areas where you will block it.
Do not stay near metro station entrances for instance.
Don't look hesitant in the metro
Tourists, on the other hand, can be seen looking anxiousely at the metro map, afraid to miss their stop, or stop at every station corner, wondering where they have to go.
Look sure of yourself, even if you are not.
Missing a metro station is generally not much of a problem: you can go back one station or go out and walk. Stations are not far from another.