In Spanish, the letter l is pronounced exactly as in English. When two of the letter ls are together, ll, the pronunciation is similar to the letter "y" in English.

l
buenos colegios
     good schools
reloj nuevo
     new watch, new clock
Juan lavó la ropa.
     Juan washed the clothes.
Yo limpié la cocina.
     I cleaned the kitchen.
¿Trajiste los boletos?
     Did you bring the tickets?
ll
unas llantas
     some tires
¿Alguien me llamó?
     Did somebody call me?
Pero yo llegué tarde.
     But I got there late.
Juan encontró las llaves que necesitabas.
     Juan found the keys that you needed.
Ellos no lo pudieron traer.
     They could not bring it.