Visit a music website such as americanmusical.com or musiciansfriend.com to price and research recording equipment for the studio you plan to build. Invest in good equipment if you plan to do some serious recording.
Purchase a desk made for holding studio equipment and monitors.
Choose the room you want to use for your recording studio.
Line the walls and ceiling in the room with acoustic foam insulation. Follow the instructions included with the type of acoustic foam/insulation you use.
Assemble your recording desk. Place it where you plan to work.
Place your recording equipment and monitors on the desk. If the desk is made for recording it will have designated stands for your monitors.
Connect your monitors to your recording equipment.
Connect all stationary equipment, such as the beat machine, sampler, keyboard, to your recording equipment with cables following the manufacturer's instructions.
Connect microphones with pop shields as needed.
Connect all your other equipment and use surge protectors at all power supply junctures.