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