One question I get a lot is, "when you're writing a song, what comes first the music or the words"? Typically, the music comes first for me. I'll be working in the lab (I'm a scientist by day) and around 10am, almost like clockwork, I start getting musical ideas that just pop into my my head! They call this period of musical lucidity as "being in the zone". I'm sure that's how the creative brain works...every artist, writer, etc. has a time of day where their brain is flowing without effort. It also occurs when I go out for long runs...whether it's the endorphins from the running or the rhythm of my running shoes hitting the pavement, I start to get all kinds of ideas for melodies, beats, and bass lines. Unfortunately for me, the lyrics don't come as easily. A lot of times I struggle to find topics to write about. I know, I know...there is so much going on in the world today (and has been for ever) that it is hard to believe that one can't find something to write about. But the problem is that when the music comes first it usually has a mood or feeling of its own and can't be paired with just any lyric and so you spend time thinking about what is the right topic for that melody or that bass line. So you end up spending a lot of time thinking about how the music makes you feel...this is called writing from inspiration and most professional songwriters will say that this is the least effective/productive way to write a song because you're dependent on when inspiration will hit (although it can result in more moving songs). The other problem when you have the music first is that you need to find words and phrases that will naturally fit with the flow and rhythm of the music. It may take a while and a lot of effort, but eventually I'll find the right words to fit the music and the right story to fit the mood.
I've also tried, to make the effort to write the lyrics first and this is equally as difficult, especially when you don't have something to say that is coming deep from within your soul, a story that you are dying to tell or words that show your empathy to common human emotions and situations. But like any story, it always starts with an idea that can make itself evident to us at the most unknown and unexpected times (and that's why songwriters have little notebooks scattered all over the place). And then after a while you'll have a collection of ideas, words, phrases, story lines that you can try to pair up with the musical ideas that you've hopefully been capturing over time (thank goodness for voice recorders on iPhones). This is a method of writing lyrics that I personally need to develop more as a craft.
The best scenario however is what I call the perfect storm which is when words in a phrase will take on a life of their own (at least in my mind) and "come along " with the music! When this happens, it's almost as if the words and music feed off of each other and themselves, to where you are getting all kinds of lyrical ideas fitting perfectly into musical patterns. This can happen quite often, but you just have to teach yourself to recognize and capture that moment and put it into words...and when that moment is something lively, exciting, moving or related to any emotion that is slightly above the level of what you're used to, that's when the magic happens, that's when the words and music appear together perfectly suited for each other. I really think this is a method that can be practiced and sharpened to the point where one can see a situation, describe it to themselves with lyrical overtones and then start crafting a song out of it. It's almost like a snowball effect...one musical/lyrical phrase will lead to another set of ideas and phrases and so on.
One thing I'm learning on this journey is that regardless of how I write, I need to always be writing, even when feeling uninspired. All writers (musical or not) have heard or read this at some point when learning writing techniques. The more you write, the easier it becomes...you create your own inspiration by starting the process (no matter how painful writer's block can be!). Combine that with going out there into the real world and experiencing life with good friends, family or even strangers, and you've got yourself a winning formula.