How long will it take to hand copy a whole book? If you can not see the goal, you lose your motivation. Let's break the time. For example, you can set goals to do what you can do in the next 25 minutes. *26

After 25 minutes you can understand more things than now. You may find something you want to know more concretely. You may have a rough picture somehow.

You get the more concrete answer for the following questions than 25 minutes ago:

What you understand

What you do not understand

What you want to know more

What you are not interested in so much

If you do not get anything, that book does not match your needs or level.

*26 I take "25 minutes" from "Agile Time Management" (written by Staffan Nöteberg), but the length is not important. For example, if you are going to take a 35-minute train in commuting, it's a good idea to do 35-minutes task. I introduce more about Pomodoro technique in (2.3.2.2) Pomodoro technique.