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