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