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