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