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