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