You may also click Select Categories to Budget at the bottom of the budget window, or right-click a category name to add or remove budget categories.
Categories you add to your budget appear in bold lettering. For example, Auto. If you add a subcategory, but not its parent category, only the subcategory appears in bold lettering. For example, Auto: Fuel.
Categories you remove from your budget aren't deleted from Quicken; rather, they're simply removed from your budget. Any transaction amounts assigned to those categories will be added to their respective Everything Else category group totals.
If you want to add a category to your budget that doesn't exist yet, choose Tools menu > Category List, then click Add Category. After you've created the new category, return to your budget and click Select Categories to Budget to add it. You can also add categories from Quicken's preset list of categories.
If you'd like, you can add and remove category groups from your budget.