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