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