all very good suggestions.
Another simple solution would be to have a system that is always the same:
@word%!%2315184@
as in: symbol - word - symbols - number corresponding to the word used in part one - symbol.
Or some such thing. By using the same word/numeric representation of word, you are quite likely to remember the password.
I had a period of using phrases that are always remembered together with an ampersand:
frankie&johnny, macaroni&cheese, bonny&clyde, hugz&kisz adding symbols and things.
I also had a mathematical period where I used squares and cubes together with words.
So a password might well look like this:
&&7sq49!magnesIUm&&
and then I could just change the number to square use a different element for the second part - systematic, yet difficult to hack.