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