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