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