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