Here's my attempt at some redlining for ya ^^
Tried to make your sketch fit the redline better aswell.
Whats great is you already have an idea about the general body type cheetahs have, such as a thinner body, thin legs & tail, etc.
But there are a few things to know, such as how the snouts of large cats slope downward, rather than poke straight out like canines-
click clickAnd how the back slopes in a wave fashion, in addition to there being no 'chest' to
all large cats (from the side, the shoulder cuts your view of the lower part of the neck)-
click^ Above example is using a leopard, but the same general rules can be applied.
Also, here are some wonderful comparisons between various big cats & others-
clickMade it so you can edit this further if you'd like