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