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