Well, first you need to locate your UserData folder: it is either in your Document folder (...\Documents\Automobilista\userdata\yourname), or in the game folder itself if you run the game as admin (...\steamapps\common\Automobilista\userdata\yourname).
In this UserData folder you'll see a folder with your name: that's were all the datas are stored. Move this folder to your desktop: next time you'll fire the game it will ask you to create a new profile.
If you want to get back your settings, lap times, etc.: close the game, open the old profile folder that you just saved. You'll find a bunch of .cch files (your lap times and records are stored there), a Controller.ini file (your wheel or controller settings are in there), a 'Settings' folder (all your setups are in there). Move them in the new user folder you have with the new profile to get them back.
I'm just not 100% sure keeping the Controller.ini is a good idea as the new one might bring newer options; it might be worth re-assigning your keys, and start fresh.