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