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