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