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