First of all, do you know how old the Artex is? Any textured coating including Artex that is more than ten years old will most certainly contain asbestos, in which case you will have to seek professional advice. You have to be licenced to remove and dispose of asbestos. If it is less than 10 years old it could still contain asbestos as old stocks were not withdrawn. If you are certain it does not contain asbestos then you can either chipt it off or use an electric samder to smooth it (but this creates a lot of dust). The easiest way is to plaster over it and make a new smooth surface, or batten and plasterboard it.

You will find an article on artex and how to remove it in the Answerbank Home and Garden article archive. Click on article 1768