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