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