Install a MIDI sequencing program if you do not already have one. You can sequence MIDI notes using most digital audio workstations, like Cubase, GarageBand, Logic and Pro Tools. You also can choose from among many free programs that support this function, such as QTractor, LMMS and Rosegarden.
Connect your keyboard to your computer. Sequencing refers to the process of inputting individual notes, so connect a digital or MIDI keyboard. You can purchase a MIDI USB controller, a keyboard that connects directly to your USB port, or you can use any traditional MIDI keyboard. If using the latter, connect a MIDI USB adapter to your PC, and connect the keyboard to the adapter with a MIDI cable. The cable connects to the round "MIDI Out" jack on the back of your keyboard and to the "MIDI In" jack on your adapter.
Open your program and create a MIDI track. While standard audio tracks record with analog sound waves, MIDI tracks are designated for sequencing. Navigate to your "New Track" option under your menu bar, sometimes under a "Track," "Project," "Create" or "Options" menu. Select the "MIDI Track" option. Sometimes it reads "Software Track," "VST Track," "Instrument Track" or "Virtual Instrument Track." Your new sequencing track appears as a horizontal bar that stretches across the screen.
Click on and select an instrument sound, a virtual instrument that corresponds with the notes played by your MIDI keyboard. Your instrument options appear in different locations, depending on the program. Some programs offer a "Virtual Instruments" or "Voices" menu on the menu bar, while others allow you to select an instrument sound from your digital mixer window, usually under the "I/O" (Input/Output) heading. Some directly display your instrument options on your main project window. Navigate to your instrument options, and select a sound.
Click the "Record" button on your MIDI track. Begin playing music notes on your keyboard. The notes transmit onto your track as sequenced pieces of digital information, resembling dots on a grid. Some programs contain only one "Record" button at the top or bottom of the project window, rather than containing a "Record" button on individual tracks.
Create a second track, and use it to record an additional music sequence on top of the original. For example, if you selected and recorded a bass instrument for track one, you might select a drum sound for track two, and add a line of percussion over your bass. Repeat this process for as many layers of music as you want to add to your composition.