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