What happens next in this paragraph?

How to avoid steep interest and penalties from accumulating on delinquent tax returns
Start with the last year you filed taxes.
Go back to the last year the irs got your taxes. You'll need figures from that return to fill out those unfiled tax returns.
Make sure you have all the tax documents the irs does. Go to your local social security office to get copies of all the w-2s , 1099s and other documents for the years you have unfiled tax returns.