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