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)(11,16)(12,15)(13,17)(14,19)(18,22)(20,23)(21,24)(26,31)(27,35)(33,34)(36,37)(1,3,5,8)(2,6,4,7)(26,31)(32,38)(33,34)(39,40)(9,11)(10,14)(12,18)(13,19)(15,21)(16,17)(20,24)(22,23)(25,26,30,31)(27,32,35,38)(28,33,29,34)(36,39,37,40)(9,12,13,20)(10,15,17,23)(11,18,19,24)(14,21,16,22)(25,27,30,35)(26,32,31,38)(28,36,29,37)(33,39,34,40)(1,2,5,4)(3,6,8,7)(9,11)(10,16)(12,18)(13,19)(14,17)(15,22)(20,24)(21,23)(25,28,30,29)(26,33,31,34)(27,36,35,37)(32,39,38,40)(1,4,5,2)(3,7,8,6)(9,10)(11,14)(12,15)(13,17)(16,19)(18,21)(20,23)(22,24)(25,29,30,28)(26,34,31,33)(27,37,35,36)(32,40,38,39)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.