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