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