1. Don't put all eggs in one basket.
Some people may just want to hold a trustworthy coin that its value is increasing, they can go for bitcoin because of this. But to make maximum profit, some people will go for altcoins, some altcoins are shit coins though, which can lead to lesser profit.
3. Don't screenshot your seed-phrase and store in your phone.
That is true but not only on phone but on all online devices, including your computer and tablets. Better offline on paper or on steel sheets
4. Be careful, some people will pretend they are bringing to you a good offer, instead, they are intentionally taking.
Especially in trading, paying trading signals. Also in HYIP and other ponzi schemes.
5. Avoid risky airdrops, don't click too many scammer links anywhere you don't trust. The scammers won't say: "Hey give me your seed phrase", they will say something unique and desirable.
Yes, airdrops can later lead to scam.