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