Work on your melodies before the lyrics. 

When I get an idea for a song I’ll write down and record on my phone as much I can. I want to completely exhaust all the inspiration in my head while in “inspiration mode.” Next, I’ll start working on my hook. The title and the part that I want my listeners to walk away knowing. Then I’ll shell in the last line of my chorus an then the verses. I’ve got more articles on that called staying out of the corner. But today I want to get into the melody. Before you start nailing in lyrics of your chorus and verse, get a melody going. While in “inspiration mode” I like to simply hum into my phone and play along with it chords I'm feeling. I'll try and determine the best tempo for the song while doing this also. But in working on the melody ahead of lyrics I find I'm ending up with better melodies. Otherwise, I end up with melodies that are tweaked to fit my lyrics. A song is music. Words set to music. so often songs go over well for listeners because of the melody and I believe the melody is often overlooked. The melody has to be interesting, memorable, singable, and engaging. Without it, I should stick to poems, right? Props to those who love poetry, but I have to music. In mentioning this I will say that when you are "inspiration mode" don't get bogged down in the trenches. Let it all fly. Toss all those words and lines down on paper, your phone notepad, recorder etc. Enjoy that wave of inspiration. I'm speaking above of the "work phase" when you take what was inspired in the "inspiration mode" and mold it down into a song.