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