To create a budget, navigate to Tools > Budget Manager.Select "New" to create a new budget. Then enter the budget name and select the "Period".Setting the "Period" as Weekly, Biweekly, Monthly or Annually will create a budget using this time period. The budget will use the "Newer" budget format.

Setting the "Period" as "Mixed Interval" will create an older style budget, which can have categories with different time intervals.

Once you have created your budget, close the Budget Manager window. Then select your newly created budget from the left sidebar (below your accounts) to access and edit it.