When it's time to move out, do another walkthrough with the landlord or property manager using your original checklist and photos to review any damage that may have occurred under your watch. Be reasonable. A few nail holes counts as wear and tear. The holes you punched in the walls do not.
Do this walk through after all your stuff has been moved out so you can clearly see any issues, and so your landlord can't come back later and say your Justin Bieber posters were covering a massive mold problem. If there are repairs that will need to come out of your deposit, get them in writing and hang on to a copy.
Once the walkthrough is complete, make sure you leave a good forwarding address with your landlord. They can't return your deposit if they don't know where to send it (and it's a lot harder for them to claim they didn't know where to send it if you can document that you gave them a good address). Also make sure you hang on to your copy of the lease, which should specify how long the landlord has to return your security deposit. Odds are you won't get the deposit back the day you move out. Typically, the landlord has a few weeks to get it to you.