How do I turn selling my artwork at home into a business?

I am making around average $1,000 a month from selling artwork. 

I want to turn my hobby into a business and continue to steadily increase my income and be able to grow my business so in maybe 5 years I can own an art gallery.

How would I incorporate my trade so I can deduct my art supplies, rent, and utillities as expenses when I file taxes.

Whats are the steps I should take? I work from home, and I already started my portfolio website.