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