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