Here's one way. Pick a word that you know you can remember easily. Use the same word as a base each time, but one time use the letters to the right instead, another time, those above to the right, another those above to the left............etc. I expect you are getting the picture!
You only have to remember one word, and the hint for yourself that you write down for each password - preferably somewhere a bit safer than your diary! - is "below R" (or whatever). Only you know the root word, which you can keep in your head - that is why it needs to be something very memorable to you that you are not likely to forget, because that is the one thing you do not write anywhere.