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