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