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