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