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