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