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