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