Songs come as they come, as the spirit moves, though sometimes circumstances determine which one you have the time or urge or leave to do first. For example, one of my most fertile periods of writing came when I had a daily commute on the DC Metro subway, and, guitar-playing being, shall we say, "unrecommended," I wrote words. Often with a tune in mind, but not always. Then when I'd get home, I'd try the tune out, chuck it and start a new one.
Sometimes my lyrics fell into such regular form that I could and did use the chorus of one song for the verse tune of another (totally unconsciously, of course) -- I had to change the newer one once I noticed the similarity. And sometimes that regularity was enough to chuck the whole lyric (it was obvious thjat no good tune could be made to follow that well-trodden scansion path, so banal was it).
I do have a problem when trying to make up tunes -- the first time through, it's new, the second time through parts of the new tune remind me of an existing song (usually not mine), and by the third time through, I'm playing that song, the pre-existing-not-mine song. I lose more good ideas that way. And I'm never clever enough to start a recording before I go through this process, since the spur of the moment is when I start playing, making preparation an after-thought.
I have found that ideas are the hard part, and the easy part, too. If you're trying to write a country-oid song, you can take any well-known phrase and make it your lyrical hook. I looked up above in the thread and saw that someone wrote "harder for me." OK, that's not an outstanding phrase, but here goes:
It's harder for me to forget you
Than it seems it is for you.
It's harder for me to make my mind up
And say the words, "We're through."
Falling in love was the easiest thing,
I'll tell you, you can take it from me.
So however hard it was on you,
It's harder for me.
That's pretty bad, and doesn't take a twist on the meaning of the words in the phrase (I could only think of something bawdy from the phrase "It's harder for me," so I went with maudlin instead), which is the more common "country" approach. I can produce a lyric pretty quickly, if I don't care what I write, but to get something good, the emotion should be deeper than the drivel I wrote up there.