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