One vertex per element, one color per generator, with an edge from x to x·s.
(2,5)(3,7)(9,10)(11,13)(12,15)(14,16)(17,18,20,21)(19,23,24,22)(25,26,30,33)(27,34,29,31)(28,32,37,40)(35,39,36,38)(2,5)(6,8)(18,21)(19,24)(25,27,30,29)(26,31,33,34)(28,36,37,35)(32,39,40,38)(10,11)(14,15)(19,24)(22,23)(25,28,30,37)(26,32,33,40)(27,35,29,36)(31,38,34,39)(1,2)(3,6)(4,5)(7,8)(9,11,13,10)(12,15,16,14)(17,19,20,24)(18,22,21,23)(25,29,30,27)(26,31,33,34)(28,35,37,36)(32,39,40,38)(1,3)(2,6)(4,7)(5,8)(9,12,13,16)(10,14,11,15)(17,18)(19,22)(20,21)(23,24)(25,26)(27,34)(28,32)(29,31)(30,33)(35,39)(36,38)(37,40)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.