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