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