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