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