Hi!I'm new in this forum.I'm spanish so excuse me if my english is bad.My cousin and I are trying to write songs, but we are very exigents and whatever song we begin we move it before finish it, because we think it is a song like each other.Can everyone tell me some advices, please?

When I write music I use to begin with the music and after I write the lyrics.Do you think music must be adapted to the lyrics or lyrics must be adapted to the music?

Siempre intenta, cuando empieces a escribir una cancion, acabarla. Aunque suene como un monton de mierda por lo menos la has acabado que es lo importante. Si nunca acabas las canciones cuando quieras acabar una cancion que te guste no vas a saber como. Esta todo en la practica, colega.

Sobre tu segunda pregunta le el FAQ sobre tecnicas de este forum. Ahi esta contestado, si tienes mas dudas despues de leerlo vuelve a preguntar.
I think whatever comes to you should be written first. Let's say you're playing your guitar(or whatever instrument you play), and you're getting some cool riffs down or you find a nice rythm. I think in that case you should adapt the words to the music. But if you are trying to come up with song ideas and you start writing, and you get these great sounding lyrics, then in this case you would adapt the music to the lyrics. See what I'm saying?