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