So owning some BTC, I thought it was time to go cold storage.
But I found hardware wallets kind of expensive, so basically made my own hardware wallet using an USB stick.

If you keep btc you don't want to lose in hot storage, I definitely suggest you following this since it gives you piece of mind.

Step 1: Download Tails, a security orianted debian distro.
Step 2: Download Rufus, or use a smiliar tool to make your flash drive into live tails disc.
Step 3: Restart your computer and run from Tails. Make sure there is no internet connection. This is your air-gapped OS where you will sign transactions. Never connect it to the internet.
Step 4: Enable persistent storage. This is where you'll storage your wallet and private keys. Enable encryption and set a very strong password.
Step 5: Create your wallet with electrum (Electrum comes pre-installed in Tails). Write down your recovery seed on a paper.
Step 6: Copy the public key of your wallet (Or write it down). Plug out the usb. Restart back into your normal OS.
Step 7: Install electrum on your normal OS and import your public key. Here you can watch contents of your wallet, generate receive adresses etc. You can't spend from this wallet, so it's safe that internet connection exists.

To spend your btc: Create transaction on your watch-only wallet. Save it into a usb stick. Boot into tails. Sign the transaction. Copy it back to the usb stick. Restart into your normal OS and broadcast signed transaction from usb stick.

Here. You have %100 safe cold storage solution, where spending btc is safe as well and only takes a couple minutes. You can plug the usb stick anywhere and have access to your bitcoins.