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