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