One vertex per element, one color per generator, with an edge from x to x·s.
(2,5)(6,8)(9,10,13,15)(11,14,16,12)(19,24)(20,22)(25,26,30,27)(28,33,36,31)(29,32,38,34)(35,40,37,39)(9,11,13,16)(10,14,15,12)(17,18,21,23)(19,20,24,22)(26,27)(31,33)(32,34)(39,40)(10,15)(12,14)(17,19,21,24)(18,22,23,20)(25,27,30,26)(28,33,36,31)(29,32,38,34)(35,39,37,40)(1,2)(3,6)(4,5)(7,8)(9,12)(10,11)(13,14)(15,16)(17,19)(18,20)(21,24)(22,23)(25,28,30,36)(26,31,27,33)(29,37,38,35)(32,40,34,39)(1,3,4,7)(2,6,5,8)(9,11)(10,12)(13,16)(14,15)(17,20)(18,19)(21,22)(23,24)(25,29,30,38)(26,32,27,34)(28,35,36,37)(31,39,33,40)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.