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)(25,26,31,35)(27,33,28,32)(29,30,40,34)(36,37,38,39)(2,6)(3,8)(10,13)(14,16)(18,22)(23,24)(25,27,31,28)(26,32,35,33)(29,38,40,36)(30,37,34,39)(1,2)(3,7)(4,8)(5,6)(9,10)(11,14)(12,13)(15,16)(17,18,21,22)(19,23,20,24)(25,28,31,27)(26,33,35,32)(29,38,40,36)(30,37,34,39)(1,3,5,8)(2,7,6,4)(17,19,21,20)(18,23,22,24)(25,29)(26,34)(27,36)(28,38)(30,35)(31,40)(32,37)(33,39)(1,4,5,7)(2,8,6,3)(9,11,12,15)(10,14,13,16)(17,20,21,19)(18,24,22,23)(25,30,31,34)(26,29,35,40)(27,37,28,39)(32,38,33,36)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.