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