How to extend my iPhone battery life?

It just drains way too fast literally by 2:30 it's at 20 percent.

Leave the Wi-Fi turned off unless you are using it and at least once a month drain it below 20% then charge it fully. Don't let all the apps run unless you are using them.

Turn everything off Wi-Fi, notifications, blue tooth everything that's on lower brightness. Nero more help go to YouTube and look up how to save iPhone battery life.