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