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