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