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