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