If you are thinking about becoming a hijabi but don't know where to start, my advise would be start with your clothing by gradually making them looser and longer. Funnily enough, this post isn't about clothing, it's about the headscarf. Converting to more modest clothes is one thing but as soon as you wrap a scarf around your hair instead of you neck, you automatically define yourself as a Muslim and this can be a very daunting experience in the Western world.The thing you have to remember is that Islam and the Quran were revealed to the Prophet (SAW) and his people in small chunks over time, if it had come down all at once, it would have been too much for any of them to digest. It's exactly the same with wearing hijab, you need to do it gradually and over time otherwise you will just bite off more than you can chew and then just turn off to the idea altogether.
If you haven't covered your hair before and want to give it a go, here is a style that I suggest, it is far more discrete than a shayla or amira style and is kind of a 'hijabi half way house':
Here are the steps: And this is what it should look like:If you are confortable with this, you could start wearing it with a polo neck top or wrap another scarf around your neck in the winter.