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