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