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