"Liberal" is one of those terms in divorce law that has no quantifiable meaning. It applies to the custody terms of your decree, describing the visitation arrangement that either you or your spouse will have with your children, depending on which of you is the non-custodial parent.
It's All Up to You
If you and your spouse agree that you'll be the custodial parent and he'll have liberal visitation rights, the two of you must maintain a reasonably amicable relationship after divorce. It will also help if you're not a stickler for ironclad rules. The phrase "liberal visitation" works in lieu of a set visitation schedule. Your divorce decree will not state exactly when your spouse will have time with the children. Rather, you may get a phone call on Thursday telling you that he wants them after school the next day and that he's keeping them for the weekend. You're expected to accommodate these requests, at least most of the time. Judges generally will not order this type of visitation unless parents have demonstrated an ability to get along and work together during the divorce process.
You May Have Nothing to Enforce
If you have problems post-divorce with your liberal visitation terms, you may be powerless to enforce a more reasonable routine unless you file a motion with the court to modify your decree. For example, if your decree includes a specific visitation schedule instead, and your ex is supposed to return your children by 7:00 p.m. on Sunday but never shows up, you can typically call the police to enforce the terms of your order. With liberal visitation, the law has nothing to enforce.