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