Flash Cards
Flash cards are a great learning and revision tools.
They are a small card with a question, image, concept on one side and then the answer, or definition, or explanantion on the other.
They are a really good, quick, easy way of checking if you can remember something accurately - they are ideal for checking recall.
The best way to use them is to have each card focussed on one fact, one item, don't put too much on them. Then draw them at random and see how your recall is. I always had them stacked by subject, topic and subtopic so I could just check out how I was doing on that specific thing - colour coding helped with this - either different coloured card, different pen, different highlight in corner etc - just some way to group them.
Here's a simple example, also watch the video there's lots of good tips in there.
There are a number of flash card websites too where you can make them on screen and they then randomise etc. These are a good addition but do tie you to a screen which may not be how you want to revise.