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