I’m not sure if you are running any custom ROMs but doing so should improve battery life as there is less bloat ware and programs running in the background. If you are not you could still try to debloat your phone as much as possible either by just deleting apps or using ADB commands.
Other than that you can have the battery saver on at all times, in settings you can configure it so that it practically never turns off.
You can go to every application and change the battery optimization to restricted (this will break some applications so you would have to put it back on optimized).
You could also turn off notifications for as many apps as possible, disable 5G if that is not a deal breaker for you, and turn off wifi/bluetooth when you are not connected to anything so it stops pinging constantly.
You could also turn off auto brightness adjustment and manually adjust it leaving it dark enough to see but not at max brightness. You should also change your phone to dark theme from light theme if you have not already done so, and change all applications to dark theme as well.
These should all marginally improve the battery life.
Another advice I can give is if you want your battery to be healthy for a long period of time, like 3 years, never charge your phone overnight where it maxes out to 100% charge. Try to keep it between 20-80%, and if possible this is controversial avoid using fast charging and especially wireless charging as much as possible. They stress the battery out a lot more than traditional charging which isn’t good for your battery health in the long run.