Some good advice I got from a HAM was to read license plates in your head using the NATO alphabet. Their letters are mostly random so you tend to see each lette

Some good advice I got from a HAM was to read license plates in your head using the NATO alphabet. Their letters are mostly random so you tend to see each letter at roughly the same frequency and it can be done daily without taking away time from your schedule. Being random also prevents you from just remembering the order of the words and actually associating them with their respective letters. After doing that for a week or two (I was bike commuting at the time), I had it pretty much memorized.