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