I think it helps to have a style & hook from the get-go. I'm still struggling with mine. For example, there are already a ton of makeup blogs out there dedicated to updating you with product release info. Will I be able to "compete" with those blogs? Probably not, since I am late to the game and don't have the access to the information they do (MU companies will provide information and product samples to certain bloggers with large followings to gain press).
So my best advice is try to find your style, don't duplicate what is already being done ad nauseum (like product release info blogs, swatch blogs, etc) unless you are privy to info that those others aren't, and have fun!
PS - If you or anyone here who has responded wants to swap links or become followers, just let me know