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