1. Use a hardware wallet. If you can't afford one, make sure your PC is clean and use an open source desktop wallet (e.g Electrum) that give you control over your private keys.
This, and actually write down the seed on a piece of paper. I can't believe how some people actually buy hardware wallets but save their seed on a .txt/word file or their mobile phone's notes app. I can't believe how people with 6-digit portfolios be THAT careless.
They think that it's secured as long as they keep the private keys/seeds on their phone but they didn't recognized that it is still connected to internet once they access to the web.
I can't understand too why they are too lazy of writing the keys on a piece of paper and paste it to any of their books or any secured storage.
It's easy and won't take that much time and effort but they are choosing to save it on their mobile phones and txt files, this practice shouldn't be adopted by newbies.