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