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