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