Ideally, it should cover all bases, including how you're dividing up property and debts, who will have custody of your children, when the non-custodial parent will have time with the children, who's going to pay child support and how much it will be.
It should also include any provisions you want to make for spousal support.
Otherwise, you'll have to go back to the bargaining table or have a judge decide outstanding issues at trial if you eventually want a divorce.
No separation period is required, but this option requires that you're both in agreement that your marriage is over, and you must state this in writing.
You can accomplish this by citing irreconcilable differences as your grounds in a divorce petition, and your spouse can confirm that you have irreconcilable differences in his answer to your petition.
You and your spouse do not have to separate first in order to divorce in West Virginia.
If you're both sure that your marriage is over, you can simply file for divorce on grounds of irreconcilable differences.
This option is essentially a court-ordered separation.