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