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