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