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