Through the use of tax-deferred retirement accounts you can invest some of the money you would have otherwise paid in taxes to increase the amount of your retirement fund. Many employers offer plans where you can elect to defer a portion of your salary and contribute it to a tax-deferred retirement account. For most companies these are referred to as 401(k) plans. For many other employers, such as universities, a similar plan called a 403(b) is available.
Some employers match a portion of employee contributions to such plans. If this is available, you should structure your contributions to receive the maximum employer matching contribution.