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