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