A schedule will help you know exactly whether you are on track to developing habits or have strayed from it. First of all, you need to plan the first day of a new lifestyle in order to stick to a similar schedule in the following days.
You need to make a list of things to do in advance that need to be done during the day. You can use, for example, Gcal.
Divide them into categories: main projects, tasks of medium importance and small tasks.
Include them in the daily schedule. You need to allocate more time to complete main projects. For example, you can use the following principle, allocate 60-30-10% of the time to complete tasks of categories 1-2-3 respectively.
You need to know how much time it takes to complete a particular task. In most cases, we allocate less time to complete tasks than necessary. Try to realistically assess your capabilities. It is also worth leaving a short break (5-10 minutes) between tasks, necessary for switching from one task to another.