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