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