Through our internet research, we discovered these existing methods:

1. Major system (numerical data) - Use a code to change numbers to phonics e.g. 1-na, 2-ta, 3-ra etc. Use the sounds to from words.
For example: 12 - if 1 is na and 2 is ta, nectar has the 'na' and 'ta' sound so we can associate 12 with nectar. If there are alot, we form words and then associate each word/

2. Imagery system (numerical data) - Associate numbers with pictures e.g. 1-candle, 2-swan, 3-tree. Use the pictures to form stories or visualize something out of them.
For example: 123 - a CANDLE burned the SWAN who was beside the TREE. This is an example of how we can associate each word

3. Split and associate (spelling/vocabulary) - Split difficult words up into 2 or more simpler words. Associate these words with the meaning of the original word to get the meaning and spelling at the same time. You can also form phrases out of the new words.
For example: diligent - dell agent

4. Linking system (sequences) - Make a small story by linking the words up in sequences. Create the short story by linking the first word with the second and the second word with the third and so on.
For example: Hat, Ball, Cat - This can be a HAT was playing a BALL with a CAT!

5. First letters system (sequences) - Form a sequence of easy to remember words by taking the first letter of each word in the original sequence and form a list of interesting and funny words.
For example: Mercury, Venus, Earth - My vital experiment
We also realize that the brain needs some organization. Also, we should take breaks and relax instead of trying to cram. We memorize better when relaxed.