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Buy what you need and then add to those as you start making different projects. Johns's selection should get you started with sign making and then you can add bits as you progress. Signs are a great way to start, it will help you get use of the design software and the use of your machine.
Don't buy sets of bits, I find that you only use a few of the bits so it is best to save that money and put it toward the bits you will use.
Your BRAIN Is The Most Important Power Tool In Your Shop. Turn It On Before You Turn On Any Other Power Tool.
A Disability Is Only A Disability If You Let It Be One