I will always add:
The morning is when the mental state is at its best. At this time, people’s brains are in a state of activation and efficiency is extremely high, so my first Pomodoro will be set a little longer, such as 40 minutes (the time for a class for elementary school students. Now come to me It is more difficult for high school students to say 45 minutes).
There used to be a popular saying, "Video games are electronic heroin." Now the elders don't say this to us anymore, but I think that now mobile phones are really drugs. When you are full of energy, you take a look at it, it's like Medusa, petrifying you. For every minute you look at it, the probability of you being able to focus immediately is halved. So if you don't want your energetic morning to be poisoned by your mobile phone, put it away from yourself. For example, temporarily put it in your bag and don't take it out. I tried it and it worked.
For me, it seems that I am not easy to give up concentration in one Pomodoro, but I often delay starting the next Pomodoro. Therefore, it is very important to establish a proper sense of planning when working. You must always remind yourself that your mind must be properly stretched, and there must be the next time!
If there is really no willpower to start the next Pomodoro, are there any tricks? It might be useful to change from sitting to standing up to work. Standing can help combat the "lazy" state.
Find a suitable time every day. For me, it may be 3 o'clock in the afternoon. Set a Pomodoro to do "important but not urgent things" in the second quadrant. This is an investment in tomorrow. Of course, if you are in good shape, you can have more than one Pomodoro.
The above experience is shared as a middle-aged person who is nearly 40 years old. Maybe your experience is completely different!