I am using Wilson Fundations for handwriting. Formation of each letter is very specific. The language used is consistent and easy to remember. The lines are as follows: Sky line, plane line, grass line and worm line.

Formation of Letters

Sky Line:  t  b  f  l  h  k

Plane Line:  n  m  i  r  u  e  p  j  v  w  q u

Plane Line Round:  c  a  o  g  s  d

Plane Line Slide:  z  y  x