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