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