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