Here are some tips from me:
• Keep Dark Mode on at all times if you don't mind.
• Go to Settings, then Connections, go to More Connection Settings and turn Nearby Device Scanning off (it wastes a lot of battery).
• Uninstall any unused apps, it will save memory and reduce the background battery drain.
• Use a darker wallpaper if possible.
• Turn off NFC, Wifi, Bluetooth and etc when you aren't using them as it will save lots of battery.
Please let me know if you see better battery life on your phone after you use these tips. Hope this helped!