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