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