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