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