As you went through your spending with an eagle eye in the last lesson, you may have found some necessary purchases that you buy regularly, like office supplies or other consumables. If you can identify anything in that category, take a moment to look into whether you could save money by purchasing in bulk.
For example, reams of paper are cheaper than individual packs. A big box of pencils is more cost effective than buying a few at a time. Make a shopping list of things you can purchase once and have for a whole year or more. If you have one time of the year that you take in a lot of payments, like the start of a new term, it may be helpful for you to purchase these items then. Otherwise, you can just purchase them as you go and plan to expect fluctuation in expenses from month to month.