Teach back to yourself or someone else what you have learnt;
Write notes. Find your best format: bullet/narrative/mind-map;
Follow connections to other materials in the references;
Set a time goal e.g. 45 minutes French vocabulary, no more, no less;
Ask questions: when attending a course or lecture listen with that aim in mind: what question/s do I need answering?;
Spend time with experts who have often discovered 'the simplicity the far side of complexity';
Learn when refreshed;
Allow and recognise the plateaus and dips of learning:A plateau is consolidation: we don't seem to improve for a while. A dip is re-wiring: we seem to get worse before we get better.