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