1. Video memorising
2. Write up on a piece of paper mode, median, mean and range and write what the mean etc. Put it on your bathroom door so when you are going to the toilet so at least 1 time a day you will be memorising MMMR.
3. Keep writing them out, so for example write: Mode is the number that accrues thew most.
It will stick in your head.
4. What you wrtite down heaps of times to remember. Record yourself saying this, listen to it over and over again everyday to help your memorise it till it sticks in your head.
5. Also listen to your recording to help you go to sleep, this will also stick in your head while your sleeping.