Congratulations on Day 1, Sarah, welcome!
My advice is not to let your head get too far in front of you. Set small goals... one day at a time, then one week at a time. In the beginning, go really easy on yourself. Don't try to take on too much. Allow yourself to be more self-indulgent than normal. Have lots of snacks and tea on hand and distractions, like TV or movies or good books.
You might also want to start a journal. Write down everything you're thinking right now, about why you need to quit. Write about all the things that you will gain from being sober. And as time goes on and you start to think about drinking again, write about that too.
Do you plan to use a method, like AA or AVRT?