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