Having a company ask for your salary history when you're job hunting can be nerve-wracking——and risky. If your salary history suggests you'll work for less than an employer intended to offer, you lose out; if your past salary implies they can't afford you, you might lose out even if you're willing to take a pay cut. Then there's the challenge of drawing up a salary history in professional resumé style that won't get your application thrown out as a sloppy mess.
Avoid the subject of money as long as possible. Never provide a salary history or a salary requirement until you're asked for one; simply state your salary is negotiable or refer to it as "mid-$30,000s." The further along you are in the recruitment pipeline when you bring up salary details, the safer you are.
Write down the salaries for all the jobs you've included on your resumé. If you can't remember some of them, check your old tax returns to see what you made in those years. If you don't have returns, contact your former employers' human resources departments for help, or just go with a good approximation.
Create a salary history using the same format as the rest of your resumé. The simplest method is to copy your resumé into a new document, rather than retype your past employers' names and your job title. Then, delete any unnecessary information such as career goals, job descriptions and education.
Type your salary figures into the new document. You can either use your salary at the time you left the previous jobs, or include your starting and ending salaries. Use the latter if you think it will show how valuable you became to your former boss.