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