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