You can just fill out the T777(S) form in Forms mode, but if you prefer to use the interview mode, here's how to get there:

1. Select Find in the upper-right area. (The Find button becomes visible after you have completed the Introduction/Profile section.)
2. In the Find window, type "employment."
3. Select Employment Expenses from the list of results, then select Go.
4. On the Employment expenses step, select Yes.
5. On the Employment Expense Profile step, make the selection that best applies to your situation, then select Continue.
6. Follow the instructions that appear onscreen to enter your expenses.