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