How to reset an iPhone without connecting to a computer?

This is honestly the truth I haven't stolen the iPhone or anything.

So I was arguing with my sister and my mum asked me to give her my phone so I put a password on it so she couldn't get into it. When she gave it back I had forgotten the passcode. I need to reset it but I don't have a computer to connect it to iTunes (mines broken). Is there a way to reset it without iTunes?

Put it in dfu mode

You can reset an iPhone through the settings windows but you will have to de-activate the find-me setting which will require wi-fi. The reset will not delete your files or settings. If you want to do a full restore, you will have to hook it up to iTunes.

Just go to your settings then General tne Reset. From there you can reset whatever you want.