You haven't worked in three years how do you explain the gap in employment?

This is difficult. You could consider a resume that doesn't emphasize dates, but concentrates on various areas of expertise instead. Perhaps you were in a situation where you could honestly justify saying that you had family considerations to attend to-- caring for elderly parents or relatives who were ill. It's particularly difficult if you were in prison. You might find employment consultants who could give you some ideas, or possibly good leads. They may be hard to find, but there are companies that are good about hiring people who are coming from that situation.