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