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