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