You may be offered a free inspection about 30 days ahead of your turn-in date, which will give you an idea of any charges you might owe for damages, serious dents or scratches. Most lease companies are pretty forgiving with such damages. You'll have a chance to fix them yourself if you choose.
On the turn in date, you take your car to a dealer that sells that brand of car, not necessarily the same dealer where you first leased. Get a receipt to show that you returned it. A couple of weeks later, you will receive a bill for your disposition charge (explained in your contract) and for any unrepaired damages or excessive tire wear. Unlike the incorrect information that "Name Withheld" gave you, you will NOT be charged for any loss of value of the vehicle.
Every car manufacturer's web site has a section on how to return their leased cars and what to expect. I advise that you go look at it.