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