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