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