how to unlock an iphone 4 to work with t-mobile?

[holllllllerwatsuuuuuup(:]

im getting a used one from my friend and its in really good condition. the problem is i have t-mobile. on my plan right now i have the internet,texting,calling,etc. but how do I get it to work with an iphone as far as sim cards and everything goes? i dont know what to do with it after i get it so can anybody please help? what is 'cutting' the sim card?

[vicecaptain]

iPhone4 suits only with micro sim. So you can get your SIM cut from any local store or you can request for a new micro sim with the same number from your network provider. Before inserting a micro sim. You must unlock the iPhone4 from the previous network provider. You can get an iPhone4 unlocked safer and easier through remote unlocking method. It is also an affordable method too. You can get the remote unlocking for an iPhone from www.Mobileunlocksolutions.com at affordable cost with easy unlocking instructions. All the best mate.