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