Joro Spoke the Truth.
No Rules.
Anything can go as long as your happy with it.
Let the song come to you, don't try to push it if your new to writing songs.
Take your time.
There is more to writing a song than adding words to a melody and music.
Let your 'Muse', your inspiration, you inner feelings, at the time do most of the work.
I use to record every practice session I ever did. I ended up with a box of over 2,700 cassettes.
Now, I have it set to record, and all I have to do it hit pause.
I recommed you have a recorder of somesort close by when you practice your instrument.
I also recommend a mini cassette recorder to carry with you when you get an idea for a title, words, theme of a song, hum a riff, hum a melody, what ever. Don't count on your memory to remember what you just thought of. You'll lose is quicker than you thought of it.
Keep your ideas in an organized file system where you can go to them when your muse has a case of the jaws at you and refuses you her help. Keep everything for a while, that you think of while working on a song. Just because it don't fit in 'My First Song' doesn't mean it won't fit in 'My Seventh Song'.
My problem is working on other peoples stuff. Nothing I do, no words, ryhmes, melody,,,, etc, nothing, is good enough.
One my own, I'm carefree, though.
Relax, take your time on a song. Some songs take only minutes to write, others months or longer.
It's finished when you decide it is.
As Joro stated, there are NO RULES.
Follow that rule and you'll do just fine.
By the way, if you get a chance to listen to some of Joro's material, lend an ear. He definitly has a way with words.
Good luck
Oh, yeah, I reread Joro's post, about how he builds a song.
I start with a chordal arragement. If anything happens for me at that point, it will be the melody and the lyrics. In other words, I work on the chords, lyrics, melody and meter all at one time.
A Rough Draft.
I go back and edit what ever I feel is weakest in the song. Then I add tempo after I'm happy with what I have so far.
I change the tempo around for a while, listening, changing, etc till I feel comfortable with it.
Sometimes at this point I change the key or a chord or two.
Then I add the drums. My weakest area in music.
Then bass, back vocals, leads, key, harp, spoons, clapping, cursing, whatever, not in any order.
Hope it gives you an idea that anything goes. Do what's comfortable for you.
Rock On,
Boogie Down,
and Jelly Out.