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