Follow the 5 step process to complete your brain dumps for different topics of your choice.
You can also complete this is two colours. One colour for content you know and another colour for content you need to revise / that you added.
Remember these do not need to be as organised as a mind map at first. You just write down everything that you remember about your chosen topic, then you organise it, then you can change colour and add in any information that you have missed out.
You might end up with more than one version of a brain dump.