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