I found the chapter "Learning how to learn" that is helpful. So I try to introduce the summary of it.
There are ten steps to learn something.
Among step 1 and step 6 are only once steps. Among step 7 and step 10 are repeatedly steps.
Step 1 Get the general picture
You need to know what you do for learning it and find some information for getting the general picture. For example, you want to learn C#; you might find information from the internet, books, blog post, etc.
Step 2 Decide scope
You decide a learning scope in detail in this step. You might have known what you are learning after the previous step. For example, You learn a basic knowledge of C# to create a simple console application.
Step 3 Define goal of achieving learn
It's important to define a goal before you begin learning.
For example, You have learned how to create a simple console application with C#.
Step 4 Find references
You find various references to learn it from books, blog posts, experts, source code, online documents, etc. You should find many referrences rather than only one reference.
Step 5 Make the learning plan
You should find the shortest path to achieve the goal. Some references explain it too much that you want to know. You look at the table of contents of references you found, and you find common entries from them. The entries you found might be the path you have to learn.
Step 6 Filter references
To filter references is necessary to step because you cannot read the all books and blog posts.
For example, you check Amazon review and choose high-rated books from there.
Step 7 Learn how to use a minimum of one
You might create a tiny program like a "Hello, world!" and set up a development environment. One of the important things is not to learn too much about it.
Step 8 Play around
Now, you should know a basic knowledge. Just give it a try to create a program! It is important to learn through practice.
Step 9 Learn deep
This step, you might have known a part of them. So go back to references and read the chapter you are learning.
Step 10 Teach someone things you learned
You show other people you learned with a blog post or YouTube, etc.