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