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