Categories are divided into master categories and categories, the latter of which are subcategories of the masters. Examples of master categories would be Medical, Transportation and Food. The categories that fall under Medical would be Doctor, Health Insurance and so on. For Transportation, categories would be Gas, Auto Loan Payment and Repairs.
Enter budgeted monthly amounts under each category, and You Need A Budget Pro populates the Spent column using your categorized transactions from the register. The Balance column is automatically computed using the amounts in the Spent and Budgeted columns so you can see funds remaining for a given category.
Right click on a category and you will see New, Delete, Rename and Move. Use these functions to create a new master category or category, or to delete, rename or move a category. A category can also be quickly renamed by double clicking the category name and filling in the "New Name" field.
At the top of each month, you will see Available with a dollar amount beneath it. This is the amount you need to budget for, and it is based on income from the previous month - not expected income. Remember, with You Need A Budget Pro you only spend what you have already earned. And, yes, you can still use You Need A Budget Pro before you have saved a month's worth of income. To do so, enter income under the Income: Supplemental category in the register which makes the income available in the month entered. Of course, work toward accumulating a month's worth of income to begin using YNAB Pro as it is meant to be used.