The majority of employers will give you a job application that you have to fill in although you have already submitted a resume. This application is as important as resume.
Usually jobs applications request same standard information. So it's better if you can gather this information in advance. You can type it on a page and when you are at employer's office you can copy info avoiding mistakes that can appear because of emotions and panic.
You should list your past positions, salaries and any other compensations you had. Do not forget to ad list of schools you have attended and military services.
You will also be asked about duties and responsibilities for each position. This answers you should also prepare from home. Instead of trying to remember and hesitate it's better to have four or five phrases prepared.
It's also useful to include any volunteer activities like working at school newspaper or fundraisings.
Most important is to be honest. All information about you can be verified. So if an employer finds out you lied he can disqualify or fire you.