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