We paid student debt in just three years. I think it is quite an accomplishment given that we live and practice in very expensive and not extremely profitable California. What's the recipe? To have a system. Here are examples of my systems. You can play with them to fit your needs.
System 1 - manual
If your income is unpredictable, it is difficult to estimate regular extra payments yet. Therefore, just come up with a rough number that you are comfortable to have in your banking account. You can take your last three months statements (bank and credit cards) and come up with an average monthly spending. Divide your monthly spending by two. This will be your starting point. For illustration purposes, let's make it 5,000.
Select a specific day of the week when you work with your loan. For example, it can be Monday. So, every Monday check your bank account. If its balance is higher than your comfort number, then send the difference towards your student loan principle. If the balance is consistently lower, it deserves deeper investigation. Or you can experiment with a lower comfort number (e.g. $500 lower) and see if it works.
System 2 - automatic
Make a reasonable estimation of your annual income and expenses. Then divide the difference by 52 and set up automatic withdrawals from your account towards your student loan principle.
- Pick up the system but understand that the number is not set in stone. Periodically adjust the numbers based on your experience. If it is too comfortable, you probably can pay off even more. If you are always close to cash shortage, then adjust it according but don't give up completely.
- Stick to weekly rather than monthly extra payment schedule. Even couple days make a difference in interest accumulation.
- If you want to go advanced, find and download loan depreciation workbook in Excel that gives you flexibility to enter extra payments on weekly basis. You can play with it and see in real time where you are with your loan and where you can be if you change your payment numbers. It can feel very empowering and motivating.