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