THE MAJOR SYSTEM NUMBER-SUBSTITUTE SOUNDS No. Sound(s) Memory jogger 0 z,s ‘z’ sound for zero 1 t,d ’t' and ’d' both have just one downstroke 2 n ‘n’ has two downstrokes 3 m ’m' has three downstrokes 4 r four … ends in the ‘r’ sound 5 l roman numeral for 50 is L 6 j,sh,ch,soft g ‘j’ reversed is something like a 6 7 k,q,hard c or g ‘k’ looks like it can be formed from two 7s 8 f,v handwritten ‘f’ can look like an 8 9 p,b ‘p’ reversed is like a handwritten number 9 – vowel sounds, w,h,y These sounds can be used anywhere without changing a word’s number value.

Also see: http://www.real-memory-improvement.com/the-major-system-basics.html