1. Look at the trading volumes of a coins on the exchange you're interested in. Exchanges make their profits by charging trading fees. The more trading volume of the coin the more profits they get out of it.The lower the trading volume of a coin the higher the possibility of delisting. That way you can make some predictions.
2. Subscribe to the news of exchanges you're interested in. They usually send notifications before delisting coins from the trading list or adding new ones. That way you'll be aware about delisting among the first.
3. Follow the exchanges' social profiles. They also often post their plans for delisting there.
4. Some of the issued tokens are security tokens. More recently, these tokens are being removed for regulatory reasons even if they have a big trading volumes.