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