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