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