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