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