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