In this situation, you sit down with your spouse on a Saturday morning, make a pot of coffee, and work out an arrangement to divide your earthly goods; accounts, photographs, art objects, firearms, exercise equipment-everything must go!
Next, you negotiate who has to go out and get a job, who has to pay spousal support, and for how long, and so forth. If you are able to get through these initial matters, you move on to the most important one; child custody and parenting time. By that point, if you haven't dissolved into screaming, you are both in a state of caffeine overload!
The next step is to bring in a lawyer to prepare and file legal pleadings and motions; prepare court orders, and assist you through the judicial process. Or, you can go online and try to do-it-yourself approach to filing.
In the short term, this is the "cheapest" option, but think about it: If you and your spouse are able to fairly negotiate issues like property division, alimony, and child custody, then either (A) your relationship is so healthy that you don't need to be divorced, or (B) one partner is leveraging the other to accept the short end of the stick. Usually, it's option (B). Hint:: Usually, the spouse who is most anxious to save money on lawyers is the one doing the squeezing, and the spouse who is reading articles like this one is the one getting squeezed.
The partner who wants the marriage to continue usually exacts a heavy price on the party who "needs" a divorce the most. It's not always a conscious choice; it's just human nature. That is the downside of a "kitchen table" divorce. They are cheaper for the primary breadwinner, and they are usually lopsided in favor of the dominant party in the relationship, ie., the primary breadwinner.
Before you choose this route, you need to get alone with yourself and ask which of these applies to you. If you are the one asking, the odds are that you are the one getting the short end. I know, I know, you don't want to spend a pile of money on lawyers, but there are better and more honorable ways to split up than this one.