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