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