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