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