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