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