How to get into an iphone that's locked?

My sister changed her password for her iphone and can't remember it I told her not to try and unlock it after it had been disabled for 5 min I was thinking about taking her to the apple or AT&T store please help As soon as possible I think the best thing to do is to take her to the phone store but I need help thanks

Try connecting to itunes on your PC and restoring it from there

1) Wipe the phone so its reset back to factory.
2) Remember your password.

Those are your 2 options.

Take it to an apple store or a shop that fixes phones