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