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