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