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