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