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