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