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