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