What can I do if I forgot my phone pattern and it won't restart

[hafsuu]

My brothers forgot his pattern and I wanted to do a factory reset but it just turn right back on 

So what should I do

[justmehere179]

Hard reboot -> press and hold all three side keys until screen goes black. Once black press and hold the Vol down key and power key until logo pops up -> release the keys for a second or two and remain pressing -> menu should pop up and factory reset is about halfway down in menu

[justmehere179]

Even upon restart you will have to log in to a previously used Google account. This is to prevent theft of devices

[realaud]

Yes, but they will still be able to set a new pin/password/pattern.  They said they forgot the pattern, not their Google account password.  Factory resetting the phone erases all security until it's re-established.