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