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