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