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