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