You need to request a trial from the judge.
The above is a general answer and is not considered legal advice. You should contact an attorney before proceeding to take any legal action, signing any papers or upon service of a summons.
If you have settled your case you must attach the written stipulation so that the judge and court clerk will know what to approve. They will also read it to make sure that it is in general compliance with the law. The judge will not fill in blanks unless you have a hearing and a decision is made.
What do you want the judge to decide? If you and your spouse have agreed on all the issues, just write it up, both of you sign, and that's that. If your STBX doesn't want to sign anything, or disagrees on what the terms should be, then write that up and submit it to the court. The Court Clerk will probably have the both of you come in to hash out the details, and if that doesn't work, then you get a judge to decide for you. But you at least need to show that you have made a good faith effort to resolve all issues before getting the judge involved.