Wondering where to write in business items such as Tools, Clothing/Uniforms, Products for Demos, Decor/signs for business, and items donated

Here are the steps, assuming this is for self-employment (not a W2 employee):

1) Go to Federal Taxes on the top menu bar

2) Go to Income & Expenses

3) Next to Self Employment Income, click Start. 

The expenses interview will cover most common expenses; you may have to click the "less common expenses" link and enter some expenses within Other miscellaneous expenses.

The link below has additional tips for self-employment and side businesses:

Reporting Self Employment Income

Hope this helps.