TokenTax connects to Coss for easy crypto-currency trade tracking and tax filing.
On Coss, click Account -> Trade History (https://www.coss.io/c/accounts/completed_orders).
Click on Export Complete Trade History.
Select a date range between before you opened your account and now and click on Export.
Upload your CSV file to TokenTax (https://tokentax.co/import/csv).
TokenTax does the hard work so you don’t have to.