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