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