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