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