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