hello readymade coloured contact lenses are available at many optical shops you can contact local optician

You should first get trained yourself how to use it,so consult ophthmologist who will train you how to keep in solution & how to insert & remove from eyes ,this is very important step before going for any contact lens, usually it hasn't to be used more than 5 hrs keeping hygiene point in mind because eyes are very delicate & important organ of our body, with regards Dr Arjun kr Singh Patna.

You should go to any eye surgeon..most of us are prescribing coloured lenses. It is not advisable to pick them up from optical, because they have to given according to your corneal shape. Too tight or loose lenses can harm your eyes.