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