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