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