You don't have to immediately go from undergraduate to graduate school. You can return to graduate school later, when you feel ready. After all, you may decide to pursue a career or a family, or you may simply need a break from school.
With your status as a returning student, you'll follow the same steps as someone who's applying to grad school as an undergraduate: You'll submit your transcripts and GPA, take the GRE, get letters of recommendation, and submit an application.
As a returning student, consider these tips:
Renew any friendships or acquaintances you have from school. You might visit or write to faculty. You basically are looking for candidates for your letters of recommendation.
Consider taking a few classes if you have been out of school for a while. This will help prepare you for returning to school. It may also refresh or remind you of some of the basic information you need to know.
Decide how much help you need with the GRE. It's usually best to take this exam while in college when all the content you study is still fresh in your mind. If you have been out of school for a while, you may need to prepare more extensively for the GRE.
When you write your essay or statement, account for your time away from school. Even if you were staying at home with a young child or working at a dead-end job, look at the skills and accomplishments you gained from these experiences. Staying home with a young child may have taught you time management. You may have connected and bonded with other parents and learned key coping skills. Try to present your experiences in a positive light that shows some connection or usefulness to the new path you are pursuing.