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