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