Click on 'Custom' and select a date range for all your trades
Click on 'View' and then click the 'Export' button
You will receive your CSV file via email
Save the CSV file on your PC and upload it here
Bitfinex's Export date is currently broken. Please use DD-MM-YY as export date and check on the next page if the date is correct. In case it's broken, use YY-MM-DD instead. Please note that the Bitfinex CSV file does not contain the settlements and fees in a third currency, only the Bitfinex API does.