You also need to identify in your writing what reading you have used - as a theoretical base, discussion point etc. The small cards can encourage the use of key words. In terms of understanding, remembering, using information, key words notes by the learner, seem to be the best form of notes. These seem to be useful - especially for general planning and specific planning for written work. Some people use them successfully for lecture notes too.
Many people use a mixed formal.
Listening to lectures etc. This also helps concentration. If you don't hear what you had expected, this also helps as a comparison basis. The way that memory works means that the beginnings and ends of things are usually easier to remember than the middle. Again, key word notes and links make listening easier.