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