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)(11,17)(12,16)(13,18)(14,15)(19,23)(20,22)(21,24)(25,26,31,35)(27,34,30,32)(28,38,33,29)(36,40,39,37)(1,3,5,8)(2,6,4,7)(12,20)(16,22)(19,24)(21,23)(25,27,31,30)(26,32,35,34)(28,39,33,36)(29,37,38,40)(10,15)(11,18)(16,22)(19,24)(25,28,31,33)(26,29,35,38)(27,36,30,39)(32,40,34,37)(1,2,5,4)(3,6,8,7)(9,11)(10,13)(12,19)(14,18)(15,17)(16,21)(20,24)(22,23)(25,29)(26,33)(27,37)(28,35)(30,40)(31,38)(32,36)(34,39)(9,12,14,20)(10,16,15,22)(11,19,18,24)(13,21,17,23)(25,27,31,30)(26,34,35,32)(28,36,33,39)(29,37,38,40)(1,4,5,2)(3,7,8,6)(9,13)(10,11)(12,21)(14,17)(15,18)(16,19)(20,23)(22,24)(25,30,31,27)(26,32,35,34)(28,39,33,36)(29,40,38,37)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.