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