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