Technically, a divorce is started by the filing of a petition, in the Family Court (they’re called Family Courts in Texas, but they could be called something else in your state).

To get a divorce started, call and get a consultation with your attorney, who will gather from you the required information, such as, the parties’ full names, the date of the marriage, the correct addresses, whether or not there are minor children, and if so, what are their names, etc. There will also be some indication of what is going to be at issue in the case, and you want to go over all of this with the attorney. If you recite in the complaint that the marital property INCLUDES

The marital home, located at 235 Shady Lane, and
A total of 3 automobiles (a 1956 Thunderbird, and a 1994 Volvo, and a 2019 Chevy Truck), and
Miscellaneous personal effects of the parties.

You have given the other side notice (made them aware) that you believe that these items are to be divided by the judge at the trial. If you don’t mention the ’56 Thunderbird, you might not be able to claim an interest in it when you get to the trial (“Judge, that was the husband’s car for ten long years before he even met her. That’s his SEPARATE property, and he retains it, and she has no claim, she didn’t even mention it in the complaint in this case. If she had, we would have disputed immediately that she had any interest….”)

All of this will be put into a document that is called a “complaint” or a “petition” (they mean the same thing), which will be filed with the Court Clerk, and then assigned, by the Clerk, a case number. After that, a copy of the filed document needs to be served on the other party: that means that someone (not YOU: someone reliable, like a deputy sheriff) will do two things:

Put a copy of the documents (the petition/complaint AND A SUMMONS) into the hand of the other party (not leave it in the door, not drop it into a mailbox, but put it in their HAND. They’ve got it. They now know they’re being involved in a lawsuit, and they can’t say they didn’t know. It was put in their hand, period.)
The person who served (delivered) that document to the other party will file another document, in the Court, called a “Proof of Service”, which is an affidavit (a written statement under oath), saying, in effect “I, Larry Smith, a duly appointed deputy sheriff, served John Jones with a copy of the summons and complaint in this case, on the 1st day of May 2019, by personal service (signed, L. Smith).”

We didn’t mention the Summons, but it is a document issued by the Court Clerk that says

“You are now being sued. If you want to file an answer or dispute anything in these documents, you’d better file an answer with this court within 21 days, and, if you don’t file an answer, the person who sued you is going to get what they asked for from the judge.”

The person getting served gets that summons along with the complaint or petition.

The deputy gets paid for serving the other party and filing that proof of service, and guess who pays it? You do, through your attorney’s office, about forty dollars, as things stand now. Frequently, an attorney will ask you (if things are going fairly smoothly between you and the other party, I mean, you talked to her, she agrees the marriage is over, we’d better get this thing started, so let’s get with it…) if the other party will just come into the office, and pick up her own papers, and avoid the potential embarrassment (and expense) of being served by a deputy. It’s a common practice and indicates a little courtesy by the suing party, which can help in the long run. Talk about it with your attorney.

In any event, your divorce is now started.

Good luck with it.