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