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