Curtain - nClothe

 1. create a geometry

2. select the geometry and got to FX > nCloth> Create nCloth

3. select some Vetex points as the image, and go to nConstraint> Transform Constraint

4. Set the timeline, let the points move together for the effect

5. let it simulate

6. stop at the point you like the clothes' look and ctrl+D duplicate the geometry

The curtain was Done!

I also use this technic for bed sheets as well.