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