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