All the tips in this topic are great and very informative, should be compulsory for new crypto users to read and apply it. I would add one more tip:

Don't use closed source wallets, and especially never store large amounts of money in closed source wallets

This is not that much of a problem for people who only use bitcoin, because bitcoin has been around long enough so that most of the popular and established wallets like Armory, Electrum etc. are fully open source. But if you're like me and also use other coins and tokens, there's not that many options. The popular multiwallets are all closed source. There is never full source code for the current version on github, if you check it it's just pieces of code, or maybe code for some old release. I personally don't trust wallets like that, because I can never have 100% confidence in what happens to my private keys, where are they send, who can see them and so on. I currently use HODLER wallet because it was the only multiwallet I could find that you can go to github and compile the application from the source code by yourself.