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