I'd start by having a look on the BFTA website to see which Region your new club would fall into
Then contact the secretary of that region, they'll be able to help you get things up and running.
Also drop Lyndeen Calvert (BFTA Development Officer) an email.
All you need to do is find some members, form a club - elect a Secretary, Chairman, Treasurer and come up with a constitution (or just edit one of the other clubs constitutions in the Region)
Once you've got a club formed, you can get get some insurance and then away you go.
As regards to subs etc.. well, I'd see how many member you're likely to have, figure out your costs and have a meeting to decide how you want to work your finances.