finding my twitter feed

i have just started posting on my blog http://www.sneakpasture.com and i see my posts are automatically showing up on my twitter page @sneakpasture. this is good but i want to customise the text that appears in twitter. problem is i can’t figure out how i set up this feed in the first place. my only activated plug-in wouldn’t do it. i’ve looked into my FeedBurner account which runs my email and RSS subscription but there is nothing specifically about my twiiter page in there either. Can you tell me how i can check how this is set up?