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