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)(11,21)(12,26,30,35)(13,19)(14,18)(15,20)(16,23)(17,28,36,29)(22,37,39,31)(24,33)(25,32)(27,34,38,40)(3,8)(5,6)(9,11,13,23,15,25,14,24)(10,16,18,21,20,33,19,32)(12,27,28,22,30,38,29,39)(17,34,35,31,36,40,26,37)(2,5)(3,8)(6,7)(9,12)(10,17)(11,22)(13,29)(14,28)(15,30)(16,31)(18,26)(19,35)(20,36)(21,34)(23,27)(24,38)(25,39)(32,40)(33,37) 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.