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