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