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