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