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