In Benny's Language Hacking Guide, he recommends writing a blog (p. 51).
There's just one massive problem with his suggestion.
He suggests you do it in your native language.
One of the most important things you can do when learning a language is to maximize your exposure to a language. And exposure is a zero-sum game; the number of minutes in which you can use a language each day is limited, and every minute spent doing things in your native language is generally a wasted minute as far as language learning goes. And that goes for blogging in your native language as well. (Yes, many of us language bloggers are guilty of this sin, but let us take the hit instead of you.)
But that's not to say you shouldn't be blogging. In fact, blogging is great; you just need to do it in your target language. And Lang-8 is set up perfectly for that. Even on day 1 in your language learning, go on Lang-8 and try to put something up there. It might just be some stupid dialog you remixed from some basic phrases you studied. It might be "My name is Vincent. I am an American. Pleased to meet you." It might just be some random sentences you tried to cobble together. It doesn't really matter as long as you're using the language.
Benny suggests using blogs as a motivating force; with all sorts of eyeballs on you, you won't be able to slack. But if all you can write is "My name is…", how can you possibly convey to people the goals you're trying to get to with such limited language on day 1 so that they can then press you to stick to those goals? You'd be surprised. It won't be so hard to write something like "I am learning English. I will write five sentences every day." Give it a shot, and then put it up on Lang-8. They'll fix it for you (especially if it's short, which it probably will be). And it's easier to get readers on Lang-8 than it is on some external blog; Benny suggests commenting on other blogs to get more readers, but this just means more time spent using your native tongue.
By diving into the target language up front, it won't be long before you can enunciate your goals more precisely on your own in your target language, without the time suck of maintaining a blog in your native language. Doing it as Benny suggests will only take you longer to get to that point.