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