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