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