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