If a token goes down I think the best to do is to wait because if you are going to sell it in the market theres a possibility of losing of it,
so just wait for the little bit of time to sell it to be profitable enough.
This is the most logical way of doing things. You're better off waiting for the price to come back up. Depending on the project and the reputation of the token, it would be just a matter of time. I would suggest though to re-evaluate the token. Because if it doesn't seem to be working out, maybe you can wait until it goes back to its normal price, then sell.