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