Ragging is a very easy way to add interesting textures to your wall. It is very easy and doesn't take lots of time to do. The patterns are caused by rubbing a cloth through a thin layer of coloured glaze. Although not impossible to do by one self, this task will probably be easier to complete if you are two persons, one to apply the glaze and the other to use the cloth.
All you need is base coat paint, collared glaze paint and a piece of nicely textured cloth. First you apply the base coat and allow for it to dry thoroughly. Evenly apply collared glaze one a small area on the wall. Bundle up a lint free rag in your hand. Roll the rag in random directions through the collared glaze, while it is still wet, until it starts to form a pattern. If the glaze starts to dry before your pattern develops, dampen the area with a sponge. Allow all the patterns to overlap to avoid open spaces. When the rag starts to loose effect, replace it with a new piece.
This technique looks best on walls or flat areas as it is the best way to see the patterns clearly. It is very easy and do not consume much time. Different sorts of cloth will make different patterns. You can try out all kind of cloth one a sample area before you start. Choose the pattern you like the most. And have fun.