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