I usually try to prevent high loss by using stop/loss when trading.

Setting a stop/loss 5% under buy price usually works for me, if market crashes you only lose 5%...

still I think most losses can be prevented by doing research about the coin you are willing to invest in.

I also use some free software that predicts the future market of several coins. www.cryptoforesight.org

With such a speculative market it is hard to exclude the risk of loss entirely.

But in my eyes if you take time to do research and also use features such as stop/loss when trading, losses can be reduced to a minimum.