Ask HN: Taxes and Bookkeeping for freelancers - What is your set-up?

In the US it is tax time, and as a freelancer (sole proprietor) I am looking to revamp my bookkeeping and tax methods. Currently I use no bookkeeping system and I figure my taxes at the end of the year, which is always tragic, realizing how much I need to pull out of savings. I want to smarten up and adopt a wiser method. Please share your set-up if you have one that is working well for you in a similar situation.