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)(11,14,17,18)(13,20,22,16)(19,21,24,23)(25,26,30,33)(27,31,35,29)(28,32,37,40)(34,36,39,38)(1,2)(3,5)(4,6)(7,8)(9,11)(10,14)(12,18)(13,19)(15,17)(16,23)(20,21)(22,24)(25,27,30,35)(26,29,33,31)(28,34,37,39)(32,38,40,36)(1,3,4,7)(2,5,6,8)(10,12)(11,17)(16,20)(19,24)(25,27)(26,31)(28,34)(29,33)(30,35)(32,36)(37,39)(38,40)(9,12,15,10)(11,18,17,14)(13,20,22,16)(19,21,24,23)(9,13)(10,16)(11,19)(12,20)(14,23)(15,22)(17,24)(18,21)(25,28)(26,32)(27,34)(29,38)(30,37)(31,36)(33,40)(35,39) involution — undirected(9,14,15,18)(10,17,12,11)(13,21,22,23)(16,19,20,24)(25,29,30,31)(26,27,33,35)(28,36,37,38)(32,39,40,34)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.