How many are in your local group?
We started our membership roster a few weeks back and so far have 20 registered members (to be honest, the number of true zeteticists in our group may be lower - I get the feeling a few people are in it for the novelty value - and the badges and shirts). We're picking up new faces all the time though.
Basically, in terms of your own chapter - you need a good public speaker, someone well versed in FET and able to command a crowd. Hold some energetic seminars. As far as merch goes, T-shirts are a nightmare - unless you have demand in the hundreds from the start, you probably won't break even on sales. Badges and stickers are the best fundraising merchandise.
Then again, decking out your full members in cool uniforms does have its allure, in terms of publicity and general pazzazz.
Make sure you keep it active. You need dedication - meet every week, plan field research and keep recruiting members and sustaining interest.
At seminars and talks, you're bound to get globularist hecklers and naysayers. This is good. It's great opportunity to let FET shine and make your critics look stupid - imagine the newbie threads on this forum about circumnavigation and gravity , happening in real life during a presentation, and then slating them in the flesh. It's awesome.