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