You will fill out the above-listed documents, file them with the court, and serve your spouse copies of the documents. If the divorce is uncontested, you can file a joint petition with your spouse. A joint petition simply means both parties are seeking a divorce. It does not mean the parties agree on all of the facts of the case, property division, and child placement/custody. Filing a joint petition will also eliminate the need to hire a process server to serve the divorce paperwork.
The initial documents to get a divorce started can all be found on the Wisconsin court system website.