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