Summarize:

Using a piano or virtual keyboard app as a guide, start by practicing a simple C major chord. For the note C, sing "one;" sing "three" for E and "five" for G. Sing "one" together at C, then have one person sing "three" at E while the other 2 hold the C. Then, have someone sing "five" at G while the other 2 hold a C and E, respectively. After practicing C-E-G, try other combinations, such as G-B-D and F-A-C. If you're practicing with 1 other person, just work on 2-part harmonies. perfectly to avoid getting distracted by other singers. It's easy to get distracted by other singers when you're harmonizing. The key to sticking to the harmony is to learn your part inside and out. Work measure by measure to commit each of your part's notes to memory. If you're in a choir, don't rely on others in your section (such as other altos or baritones) to stay on track. Additionally, don't assume that you'll always be surrounded by other members of your section when you perform. If you have trouble sticking to your part, practice singing with a recording of the melody. Play it softly at first, then gradually increase the volume. The best way to learn how to harmonize is to sing with others in a group. Look for a choir or chorus group at your school or place of worship, or look online for one in your community. If you're a soprano and want to harmonize better, try to join a choir as an alto. Sopranos usually sing the melody, while alto, tenor, and baritone sections sing harmonies. While apps and other resources can be super helpful, nothing beats working one-on-one with an experienced voice teacher. In addition to harmonizing, a voice teacher can help you with other singing techniques, such as breath control and vocal health. Additionally, consider taking classes in music theory to learn more about how harmonizing works.
Practice singing chords with 1 to 2 partners. Learn your part Join a choir to put your harmonizing skills to the test. Take lessons from a voice teacher.