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