how do I restore the settings button on my iphone. it disappeared

Hi,

Try a Reset of the Phone... You will Not Lose Any Data...

Turn the Phone Off...

Press and Hold the Sleep/Wake Button and the Home Button at the Same Time...

The Apple logo will Appear and then Disappear...

Usually takes about 10 - 15 Seconds...

Turn the Phone On...

It can't be deleted and likely was moved to a different home screen page or inside a folder. Search for it there.

You can reset it to its original location:

Settings > General > Reset > Reset Home Screen Layout

(Note that the above instructions for resetting the phone are incorrect:

1. Do not shut down phone first

2. Press both home and sleep/wake buttons until the Apple logo appears

3. The phone restarts itself - that's what the Apple logo is indicating.)