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