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