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