Subleasing agreement

Hey all, I will be subleasing a bedroom in Manhattan and was wondering if I should look up a standard sublease agreement for both parties to sign? Is this done usually? I will be providing a security deposit equal to one months rent and just want to make sure I get it back from the current leaseholder at the end of my term assuming I dont destroy the place. It sounds like my future roommate doesn't set aside the security deposit in a seperate bank account because he said he needs mine to pay off the current roommate back. I guess that's not really a big deal. I'm new to NY and this entire process so any thoughts would be appreciated.