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