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