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