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)(12,17)(13,21)(14,15)(16,20)(18,24)(22,23)(26,31)(27,34)(29,37)(36,39)(1,3,6,4)(2,7,5,8)(10,15)(12,23)(16,19)(18,21)(25,26,30,31)(27,28,34,32)(29,33,37,38)(35,36,40,39)(10,15)(11,20)(17,22)(18,21)(25,27,30,34)(26,32,31,28)(29,35,37,40)(33,39,38,36)(1,3,6,4)(2,7,5,8)(9,11)(10,16)(12,21)(13,22)(14,20)(15,19)(17,24)(18,23)(25,27)(26,28)(29,35)(30,34)(31,32)(33,36)(37,40)(38,39)(1,4,6,3)(2,7,5,8)(9,12)(10,17)(11,21)(13,19)(14,23)(15,22)(16,24)(18,20)(25,28)(26,27)(29,36)(30,32)(31,34)(33,35)(37,39)(38,40)(1,5,6,2)(3,8,4,7)(9,13,14,24)(10,18,15,21)(11,22,20,17)(12,16,23,19)(25,29)(26,33)(27,35)(28,36)(30,37)(31,38)(32,39)(34,40)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.