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