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