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