Record the most high-quality demo of your pop song that you can reasonably afford. While some record companies might be able to discern a classic pop hit with just a vocal/guitar demo, many nowadays prefer demos as close to the finished product as possible.
Copyright your pop song. Go to copyright.gov and follow the U.S. Copyright Office directions to copyright your music. This could save you a lot of money down the road if a record company attempts to plagiarize your pop song.
Look up industry pitch sheets. These list record companies looking for new pop songs and the type of song they are looking for. You don't want to send your catchy dance hit to a record company looking for a pop ballad. Find the names of Artists and Repertoire (A&R) representatives working at these record companies. These are the people responsible for scouting new talent and finding new songs.
Contact the A&R representative by phone and ask if the record company is looking for new songs. Ask if it has any artists in need of new material. Pop artists often record songs written by professional songwriters and, if the record company doesn't want your version of the song, it might want another artist to record it. Many record companies work with established professional songwriters and might not be looking for new talent.
Hire a lawyer or manager if possible. These professionals possess the clout you might need to reach certain record companies. Most record companies that release top 40 pop songs don't accept unsolicited demos from unknowns. They consider songs presented to them from industry professionals.
Include your demo with a letter of purpose to the record company. Express your professional credentials and what artist your pop song might work for. Include a typed lyric sheet as well.
Contact the A&R rep before submitting your demo and package. Let him know you are sending your song.
Contact the A&R rep for follow-up several weeks after submitting, unless you are given instructions not to contact him.