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