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)(11,19)(12,13)(14,25)(15,18)(16,22)(17,27)(20,26)(21,28)(23,33)(24,36)(29,35)(30,38)(31,34)(32,39)(37,40) involution — undirected(2,5)(6,8)(9,11,20,24,13,22,15,31)(10,16,26,34,12,19,18,36)(14,28,35,40,27,32,30,23)(17,21,38,37,25,39,29,33)(1,3)(2,6)(4,7)(5,8)(9,12,13,10)(11,21,22,39)(14,29,27,38)(15,18,20,26)(16,32,19,28)(17,35,25,30)(23,34,40,36)(24,33,31,37)(3,7)(6,8)(10,12)(16,19)(17,25)(18,26)(21,39)(29,38)(33,37)(34,36) 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.