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