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)(11,17,18,14)(12,20,21,15)(19,22,24,23)(25,26)(27,33)(28,31)(29,37)(30,36)(32,34)(35,40)(38,39)(2,6)(3,4)(9,11)(10,14)(12,19)(13,18)(15,22)(16,17)(20,23)(21,24)(25,26,28,31)(27,30,35,38)(29,32,34,37)(33,39,40,36)(1,2)(3,8)(4,7)(5,6)(25,27,34,39,28,35,29,36)(26,30,37,40,31,38,32,33)(1,3,5,4)(2,7,6,8)(11,18)(14,17)(19,24)(22,23)(25,26)(27,30)(28,31)(29,32)(33,36)(34,37)(35,38)(39,40)(1,4,5,3)(2,7,6,8)(9,12,13,21)(10,15,16,20)(11,19,18,24)(14,22,17,23)(26,31)(30,38)(32,37)(33,40)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.