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