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