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