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