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