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