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