1. Don't send cryptocurrency to people who claim they will "double your money."
2. Double check that you are using an official website, not a malicious copy of a website.
3. Be highly suspicious of anyone who cold-contacts you by direct messaage, email, etc
We as newbie we really need to be very careful and take our time to learn
Not to rush things because the forum is very wide and full of scammers
E.g read more and pay very good attention to our high rank leaders
Learning no get limit and it's not applicable to newbies especially when it has to do with security. Everyone can fall victim to this scammers irrespective of your rank here in the forum but newbies to this industry are actually more vulnerable. Let us all be careful to protect ourselves from cyber and physical attacks.
I have little contribution to add to your points:
Not only cryptocurrency, if anyone asks you to send anything be it digital or physical currencies, properties and receive double in return, you don't have to think twice before cutting off that conversation and block the person straight. Remember, the more you keep the conversation, the high chance you become convinced and end up falling into their trap.
Limit your access to unknown websites once you start your journey in this space. Advisably, have a separate device for your daily usage and the other for your investments. This one will contain your wallets with very limited access to internet through shared links.
It doesn't matter whether someone approached you for investment or to teach you about crypto investment, trading or whatsoever, it's definitely an attempt to scam you. No serious person will message you first just because they want to teach you, you look out for them and not the other way round. In the course of looking for one, please be careful and if possible, look around your vicinity for physical tutor.
In conclusion, the first step to avoid being scam online and offline is to be contented and do away with greed. Greediness is the major factor that leads to being a victim of scam. If you are desperate to make money which you did not work for, you will definitely get scammed one day. Bitcoin is all about learning, buy, hold/trade and sell. Anything other than these, you should question where you are heading to.