If you wanted to start your own nomad base all it really takes is a change in perspective and spreading the word out there.
First of all this is a big commitment to turn your private living space into one that is semi public. With other people who have no legal binding to the house to come in and basically let it be their own. This takes a small level of organisation, but nothing much more than regular hosting of travellers take. But if you have a lot of stuff in your house you really care about then forget about it, it is probably going to get knocked off its shelf and broken.
Next, all you need to do is to inform the world about the existence of your place with your nomad base intentions, and the rest is done by simply people coming and staying. There are different ways to do that.
A very good step is to make a post on http://nomadbase.org and tell the network directly about it. If you don’t want to be dependent or limited by a hospitality network, you might even start your own website or blog for your place. After all, if you happen to be already well-travelled and have a wide network of travelling friends, it might not even take more than just telling them and them telling their friends.
You could also start hosting through usual hospitality exchange networks (like BeWelcome), although this might only get people coming for a few days at a time. But make it known that you want people to stay for a longer time, that they aren’t required to do anything in return for your hospitality except treat your place like it is their own and the people will come.
Posting messages to hitch hiking groups, telling local dumpster divers, or organising a hitch gathering to happen at your place could potentially kick things off.
Sometimes nomad bases struggle to get people to come stay at them. Being aware of the cause of this is important. It could be that your town or city has no inherent calling to travellers, especially those that might want to stick around for more than three days. Maybe the hosting attitude still is that people are coming to stay are strictly guests rather than them believing it is their place as well. Maybe you are just kind of weird or smell bad or something.