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