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