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