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