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