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