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