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