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