Quite some years ago when studying Business Administration at Cologne university, I tried a lot of different things to make my learning efforts more effective. One of the most effective things I tried was the following:
During the lectures, I took notes of what the professor said. Every now and then, I went through my notes and marked the most important key words with different colours. I then condensed my notes to the most relevant concepts from the lecture, adding more information from the recommended literature here and there and structuring everything in a meaningful way. A couple of weeks before the exam, I had my handwritten summary ready. I focussed only on learning what was included in the summary which was probably about 70-80% of what the professor had talked about. This helped me a lot to first minimize my learning time and second maximise the outcome (the result of the exam).
Building on my experience this is what you can do after a training or an online course to integrate what you have just learned:
Write your own summary of the key concepts. Just write down the titles and some bullet points for every concept.
Schedule 20 minutes once a week for a period of 1 month and then every second week for another month to go through your notes by reading the titles and trying to remember the bullet points.
This will be help you to reduce time for repetition and strengthen the neural connections in your brain in order to retain the most important key points which you can apply during daily life.
When will be the next opportunity to try out my summary method?