Roshan, the best possible route is to have a put option embedded in the equity instrument. However, given the complex nature of such securities, the Indian capital market, which is relatively immature, has never shown attention / interest in the matter.
If such a clause is not put in, then a good way is to hire an investment bank / consultant to see if there is any possibility of improving the company and / or discuss any possible exits (eg. sale to other private investors etc.)

Let me know your thoughts.