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)(11,15)(12,14)(13,16)(17,18,21,24)(19,20,23,22)(25,26,30,33)(27,31,28,35)(29,32,37,40)(34,38,36,39)(9,11)(10,15)(12,13)(14,16)(17,19)(18,22)(20,24)(21,23)(25,27,30,28)(26,31,33,35)(29,36,37,34)(32,39,40,38)(10,12)(11,16)(19,23)(20,22)(25,28,30,27)(26,31,33,35)(29,36,37,34)(32,38,40,39)(1,2)(3,5)(4,6)(7,8)(9,12,14,10)(11,13,16,15)(17,18)(19,22)(20,23)(21,24)(25,26)(27,31)(28,35)(29,32)(30,33)(34,38)(36,39)(37,40)(1,3,4,7)(2,5,6,8)(9,13)(10,11)(12,16)(14,15)(17,20,21,22)(18,23,24,19)(25,29)(26,32)(27,34)(28,36)(30,37)(31,38)(33,40)(35,39)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.