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