To say "I miss you" in Spanish, there are several ways to express it. Here are some of them:

1. Say "te echo de menos." This phrase is a common way to say "I miss you" in Spanish.
2. Use the phrase "te extraño" in Latin America. This phrase is a more direct translation of the sentiment "I miss you."
3. State "me haces falta." This is another phrase used to mean "I miss you" in Spanish.
4. Choose the correct object pronoun.

Here's an example of how to use the first phrase:

1. Start with the subject pronoun (yo, tú, él/ella/usted, nosotros/nosotras, vosotros/vosotras, ellos/ellas/ustedes).
2. Add the verb "echar" conjugated according to the subject pronoun.
3. Add "de menos."
4. Add the object pronoun for the person you miss.

For example:
- Yo echo de menos a mi familia. (I miss my family.)
- Tú echas de menos a tu novio. (You miss your boyfriend.)
- Él echa de menos a su perro. (He misses his dog.)
- Nosotros echamos de menos a nuestros amigos. (We miss our friends.)
- Vosotros echáis de menos a vuestra abuela. (You miss your grandmother.)
- Ellos echan de menos a sus hijos. (They miss their children.)

I hope this helps!