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