Soundproof the room you will use to record vocals and instruments. Tack soundproofing material to the walls like egg cartons or carpeting.
Purchase equipment. This will include audio interface, headphones, monitors, microphones, microphone cables, microphone stands and a digital audio workstation platform like Pro Tools, Sonar or Cubase.
Install the digital audio workstation platform on your computer. Connect your audio interface and monitors to your computer. Connect your microphone(s) and headphones to your audio interface. You can record studio-grade recordings using this light assortment of gear and mix your recordings on your digital audio workstation platform.
Record demos. You will need to show prospective clientele you know what you're doing.
Create a website that includes demos of your studio recordings. Post links to your studio on local message boards and forums to attract interest.
Offer your recording services for little or no cost. This will entice local artists to check out your studio.
Ask your starter clientele if they know any other local artists looking to record. Also ask if it is possible to include a link to your website on their page. This way you can further promote your studio.