Obtain a music engraving program, or borrow a computer with one already installed. This could include premium programs like Finale or Sibelius, or more basic, inexpensive or free programs like MuseScore (www.musescore.org) or Finale Notepad.
Save a .midi file to your computer. In most cases, you can do this by right-clicking a website link to a .midi file (or ctrl+mouse click) and selecting “Save target as.”
Open the saved .midi through your music engraving program. With many programs, you may have to select the .midi file format from the “open” menu’s drop-down bar of format choices; while the programs support this format type, it’s unlikely to be a default format.
Clean up the resulting notation file. Once the .midi is imported, you’ll have a rough music score automatically generated, but it will most likely have a number of errors. Go through the music measure-by measure and use your notation program’s editing tools to move any notes that are in the wrong place, fix notes that are wrong and make the layout look cleaner, if need be. Use the program’s audio playback function to help you hear any errors you can’t see: it will scroll through the display as it plays, so you’ll be able to see where they are.
Add style markings. The music produced by this conversion will not have any tempo, dynamic, articulation or other types of indicators. Use your notation software’s buttons and insert these where you think the music calls for them.
Save and print the sheet music.