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