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