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