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