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