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