No matter how much money you earn, the amount you invest each year should be based on your goals. Your investment goals not only provide you with a target at which to aim, they also provide the motivation to stick with your investing plan.

Your investment goals should also be based on how much you can afford to invest. With an income of $50,000, the constraints of living expenses may prevent you from investing as much as you would like initially, but if you stay focused on your goals, you should be able to increase the amount of your investments as your income increases.

By following four key financial planning steps, you can determine how much to invest in the beginning and have a plan for achieving your goals through gradual increases in the amount you invest. For purposes of illustration, this particular case involves a 30-year-old person earning $50,000 per year with an expected increase in income of 4% per year.

Set Your Goals

At age 30, you may have several goals you want to achieve, which could include starting a family, having children, providing those children with a college education and retiring on time.

This is a lot to accomplish on a $50,000 income. However, it is safe to assume your income will increase over the years, so you should not let your current income constrain your goals. You just have to prioritize, and as you set up your investment plan, target each goal separately. For this example, assume the goal you want to target is to retire at age 65.

After inputting some assumptions into a retirement calculator, this indicates a need for $1 million in capital. This is your target. Using a savings calculator, and assuming an average annual return of 6.5%, you need to save $500 per month starting at age 30. This is your savings goal. Your next step is to create a spending plan that allows you to meet this goal.

Create a Spending Plan

The mistake many people make when creating a personal spending plan is they determine their savings amounts around their monthly expenses, which means they save what they have left over after expenses.

This invariably results in a sporadic investing plan, which could mean no money is available for investing when expenses run high in a particular month. People who are intent on achieving their goals reverse the process and determine their monthly expenses around their savings goals. If your savings goal is $500, this amount becomes your first expenditure.

It is especially easy to do if you set up an automatic deduction from your paycheck for a qualified retirement plan. This forces you to manage your expenses on $500 less each month.

Lock in a Percentage of Your Income

Most financial planners advise saving between 10% and 15% of your annual income. A savings goal of $500 amount a month amounts to 12% of your income, which is considered an appropriate amount for your income level.

Assuming your income increases by an average of 4% per year, this automatically increases your savings amount by 4%. In 10 years, your annual savings amount, which started out as $6,000 per year, will increase to $8,540 per year. By the time you are 55, your annual savings will increase to $16,000 per year. This is how you reach your goal of $1 million at age 65 starting out on a $50,000 per-year income.

Invest According to Your Risk Profile

This investment plan assumes an average annual rate of return of 6.5%, which is achievable based on the historical return of the stock market over the last 100 years. It assumes a moderate investment profile, investing in large-cap stocks.

If you are adverse to risk or prefer to include investments that are less volatile than stocks, you will have to lower your assumed rate of return, which will require you to increase the amount you invest.

At a younger age, you have a longer time horizon, which may allow you to assume a little more risk for the potential of higher returns. Then, as you get closer to your retirement target, you will probably want to reduce the volatility in your portfolio by adding more fixed-income investments. By staying focused on your benchmark of a 6.5% average annual rate of return, you should be able to construct a portfolio allocation that suits your evolving risk profile over time, which will allow you to maintain a constant monthly investment amount.

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