Mind maps. You learn they don't have to be works of art. They can be scrappy as anything. But a word with a few marks (call them symbols if you like) can bring back details because the marks are like tying a piece of string around your finger to remember to buy the milk on the way home.
If it's in your purpose to include quotes and examples they will naturally find their way onto mind maps.
Another piece of advise... change your vocabulary your choice of words "hard work" is de-motivating and why must it be hard?
Consider it an enjoyable challenge and you'll notice it doesn't take much to get motivated. How you express yourself to others like how you write a message in your post is a good insight what you are non-consciously telling yourself about a task you face.
Hard work? Thinking so makes it so. Thinking that robs you of motivation. When you look for your purpose you're also looking for the challenge and fun you can have with learning.
Alex