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