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