We are doing exactly what you are asking about. Our first step was to affiliate with Una Voce. We then started with a small group of about 8-10 people. The first meetings of our group were focused on establishing an organization and setting up acheivable goals. Examp; starting altar boy instruction, a choir.
Una Voce provided us with a link on their website and pretty soon we began getting inquiries asking how they could help or get involved.
We are now getting ready to hold our second quarterly potluck where we invite all interested parties to come and see what we are doing.
We have produced a powerpoint presentation to take to our Archbishop whenever he lets us come up. (which so far has been a “no response”). Altar boy training is well underway, the choir is forming and practicing, and the acquisition committee has picked up vestments and altar hardware so that we are almost ready to host a TLM. Found several sympathetic priests that may be willing to help us out if we can get permission.
Our committee meets monthly at someones home. Next month we will be applying for our state non-profit status. Then we can begin to search for a church that is for sale in earnest.
Do I think the Archbishop will let us have a Mass? No; not on our first try. But as the Scriptures say about the persistant woman who kept after the King. Eventually it will happen.
We openly support our NO parishes with the understanding that when we can have the TLM, that is where we will go. So far no one has spoken openly against us. That may also change, but for now it pedal to the metal.