Personally, I for myself identified some good thoughts:
1. Do not invest all funds in one currency
2. Before you buy something, then study the coin in detail.
3. Do not listen to advice, but think with your head.
4. Do not keep funds on stock exchanges, but transfer to cold wallets. (If you buy in the middle or long term)
5. If there is a financial opportunity, then buy a separate computer / laptop for bidding and wallets. Your money is always at risk, do not go to phishing sites and pages, always check them!
Thanks to his advice, this is very useful for me as a beginner in the trader, many people say being a trader is a lot of risk (big loss), and this may be a way to avoid the loss and how to be a wise trader.