The trial balance lists all of the credit balances in one column and all of the debit balances in the other.
The trial balance is produced following the journalized and general ledger recording of all transactions for the time.
When producing a trial balance, it is crucial to make sure that all account balances are recorded under the relevant column.
The columns are follows: 

Assets = Debit balance
Expenses = Debit Balance
Equity = Credit balance
Liabilities = Credit balance
Revenue = Credit balance