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