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