1. Learn about the volatile market
2. Learn how to analyze chart
3. Take your time to practice demo trading before going into real trading.
4. Do not be greedy, take profit when it’s best to do that, do not hope to get the whole world at a time.
They have to learn first about Bitcoin, how to store bitcoin safely when they buy it. What wallet to use for bitcoin storage, how to back up a wallet and recover a wallet.
Then after learning basics, they can buy bitcoin and store it in their non custodial wallet for their investment. Let me repeat, investment, not trading.
Trading is risky and newbies are more vulnerable to lose money in trading. Even senior people in the market can lose money with trading so don't expect newbies to get profit with trading.