Can I add fabric to my supply expenses?

Yes, if fabric is used as a supply in your business you can deduct it as an expense. To enter your fabric as a supply select the following:

• Federal
• Income and Expenses
• Edit next to your business
• Add Expenses 
• Scroll down and click show more until you see Supplies and click Add Expense

@sarajbedford

Because I buy it monthly, do I add the amount I spent that month??

You are filing an ANNUAL tax return so all amounts entered in each category should be the ANNUAL total. 

Yes, you will add the amounts you spent every month and enter it as one lump sum.