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