Not quite clear what you mean -- its an open patio with a roof? It's an enclosed patio (with walls, say) and a tarp? I live in a city, and usually you just make the walls high enough that you can't see over the wall, or at least high enough that you have the illusion of privacy when sitting down. Is that possible here?

Post some pics, please.

Lattice work is the easiest. White cotton "sheer" cotton are very sharp looking (flammable so don't let them blow around into open flames). More information (ie. photos) is needed to go much further than that.