Here are the steps for sending bitcoin from your Coldcard wallet in an air-gapped fashion by using the MicroSD card.
Click on ... in the top right corner and select Wallet Settings.
Active the PSBT workflow option and click on Done.
Click on Send in the top right corner.
Insert the recipient's bitcoin address to the right of the To field.
Enter the amount you wish to send.
You can switch between BTC and USD denominations using the arrows.
Click on Advanced options to enter a custom fee rate (this can also be adjusted later).
Click on Continue.
Enter a label to identify the recipient and click on Continue.
Verify that the information is correct and click on Save PSBT file.
You can adjust the fee rate by clicking on the clipboard icon.
You have a sliding bar to adjust the fee amount depending on how quickly you want this transaction to be accepted by the network. There are several methods of looking up the current fee rate, one being.
Enter a name for the file and save it to the microSD card.
Eject the microSD card and insert it in the Coldcard.
On the Coldcard, select Ready To Sign.
Verify the transaction details on your Coldcard and confirm the transaction by pressing on the checkmark.
Once the transaction signed, remove the microSD card from the Coldcard and insert it into your computer.
In Wasabi Wallet, select Broadcast and then select the file ending in -signed.psbt and select Confirm.
The wallet might present you with tips for increasing the degree privacy of you transaction. Just hover over the shield icon in the Preview Transaction module to see what you can do.
The outbound transaction will appear in your Dashboard and the balance will also be updated.
