One of the most important things I have learnt from this forum is how to secure your digital assets.
Here are a couple  of things you should avoid after setting up your air gapped device or when installing your wallet generally;
1. Avoid visiting sites with low trust score and security warnings. These security warnings are usually displayed in your browser.
2. Use secure browsers like;
    BRAVE which you can get from their official page   
    https://brave.com/
    TOR browser which  you can get from. 
    https://www.torproject.org
    You can even make use of the local browser that comes with your OS as long as  your privacy is safe and your device is protected from malware.
3.And most importantly always get your softwares from their official pages especially when installing a wallet software. This will reduce your chances of installing a malware or getting an altered or monitored version of that software.
 Here are some official pages of some of the most secure and popular wallet softwares
 LEDGER.
 https://www.ledger.com/ledger-live
 TREZOR.
 https://trezor.io/
 MYCELIUM.
 https://wallet.mycelium.com/
 ELECTRUM.
 https://electrum.org/

And most importantly Don't forget to keep your keys safe mate😁