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