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