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