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