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