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