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