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