Here's how expenses are entered:

1.       Click Federal on the left-hand side menu.

2.       Click Income across the top.

3.       Scroll down to Self-Employment and click Show more.

4.       Click Start or Revisit by Income and Expenses.

When you get to the screen in the picture below, you'll enter those expenses under Miscellaneous.  You can itemize any legitimate expense that's not categorized.  They get reported on page 2 of your Schedule C, and carry over to line 27a.