Un-syncing from one computer and syncing with a new one

I have an iPhone 4s, which has been synced with my Mac desktop at work. However, I got a MacBook Air for Christmas for my personal use. I want to un-sync my phone from my work computer and sync it with my home laptop. I cannot find information on how to do this. Could you please give me some pointers as to how to accomplish this task? I feel like it should be pretty easy, but seeing as though I can't find information, this makes the task difficult. Also, if I lose my music from my Mac Desktop on my phone, I won't be devastated. As long as it stays on the desktop, I will be fine!

Thanks in advance for your help!