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