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