You can enter it as Other Employment Income.

To enter your other employment income that is not reported on a slip or form:

Using the online edition of TurboTax:

1. Select Find at the top-right of your screen and type “employment” into the search field.

2. Select Employment Status from the options that appear, and then select Go.

3. On the Employment Status step, select Received tips, gratuities, occasional earnings, or other employment income, and then select Continue.

4. On the Other Employment Income Sources step, enter information about your other employment income.

5. Select Continue.

Using the CD/download edition of TurboTax:

1. At the top-right of your screen, select Find and type “employment” into the search field.

2. Select Other Employment Income from the options that appear, and then select Go.

3. On the Other employment income sources step, enter information about your other employment income.

4. Select Continue.