IPhone 4/4S SIM card Problem?

My dad bought me an iPhone 4S. I still have my Samsung galaxy s ii. And I just realized that my SIM card won't fit! What can i do?

Cut the sim card and leave the yellow thing cut the plastic like the white stuff

Take your sim card down to the ATT or T Mobile (what ever sim you have) store and have them cut it(they will for free)

Also if you have a T Mobile sim you will need to unlock the iPhone in order for it to work

You don't need to cut the card. Just go to a store that sells phones for your service provider and ask for a micro sim. Either ask them to activate it, or call your provider direct and organise activation over the phone (most service providers can be called using unactivated sims)