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