I keep a notebook of my expenses and my income! Making a budget is really useful, too. You figure out how much you can spend a month on food and boarding and then don't go over that - and if you really want to save money, you can always camp out.
Oh, and don't buy anything but what you absolutely need until you have enough money to waste every now and then.
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Oh, and don't buy anything but what you absolutely need until you have enough money to waste every now and then.