No matter what your charge indicator says, your device will never actually be 100% charged or completely discharged. It is the software integrated into the phone that manages these problems. The most useful advice to preserve your battery is therefore to charge your phone on long fixed beaches in order to avoid small deleterious recharges. If you need a little boost during the day, fast charging up to 80% with a high-performance charger (provided the phone is compatible) will not damage your device, however. This will allow you to focus on habits with more concrete results.
In addition, lithium-ion batteries hate high temperatures. It is therefore advisable not to leave your phone in the sun, especially in summer, or charging in cramped places, such as under a duvet… For the same reason, and also because a battery does not like to be charged and stressed at the same time, avoid using your phone when it is plugged in. A lithium-ion battery is supposed to last about 500 charge cycles before losing efficiency irreparably. By adopting these simple reflexes, it is possible to go much further.