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