Imagery is a tool used by almost any artist in any field to create images or to spark ideas in the heads of the target audience. This helps them understand the emotions behind the piece and often better understand the artist. What is happening here is a process in which, in the case of music, a listener's brain hears a phrase and creates an image based on the lyrics. At no point did the artist describe what the image looked like, or tell the listener the significance behind the words, but his/her brain knew to create an image. Naturally, no two listener's will have the same image and it's highly improbable that any will have the exact same one as the artist, but a general sense of emotion can be conveyed in this way.
Take for example some mildly pretentious lyrics that I have written just now.
Submarines and tangerines,
Go falling through veils of green
They twist and turn and float away,
To fight and flee another day.
The important lines for the image are the first three, obviously enough, because they are the ones actually describing the scene. The last line is included to give some motivation behind the first three. The listener takes the first three lines, and perhaps imagines huge numbers of metal submarines and disproportionately large tangerines floating in a green ocean, and from the last line knows that they are escaping from something. This is one interpretation. While the image means nothing, and certainly doesn't enhance anyone's life, it has a sense of something going on beyond our control and understanding. The creator of these lyrics may now be considered a mysterious and creative person.
So how does one go about creating such images? It is actually simpler than it may seem. What one needs to do, should one decide to embark on the quest to create pretentious images, is to find a place where they can focus and just think. Don't think about images or how you can come up with cool ones, just think about things that have been going on in your life. How has your life been recently? What is the overall feeling behind the past few weeks? Have you been happy? Have you been angry? What have you spent most of your time doing? Start making metaphors. Draw parallels from your life to anything you can think of. Start naming objects that have always mildly interested you. Let's start with a simple example:
The image of stars being eyes that watch over us. Fairly simple, not a lot of thought is needed to make this image work in your head. Let's start with the first line:
All the stars were eyes
This pretty much sums up what we're going to see, but now let's add depth to it:
All the stars were eyes
Unblinking and filled with pain
We can turn this into a rhyme later but for now let's just get the next two lines in:
All the stars were eyes
Unblinking and indifferent
They saw the sins of man
And watched on anyway
This, as awful as it is, does evoke an image in your head. You probably right now are imagining a multitude of stars looking down at you, unmoving. Not too hard to evoke, and probably won't interest too many people. Let's try making it a bit more involving. If we add lines, we can make them see something specific. This will create a second image in your head and connect it to the first one:
All the stars were eyes
Unblinking and indifferent
They saw your wicked lies
And watched on anyway
They saw the brother kill his kind
They saw the mother eat her child
They watched the widow drop
And though they've seen the death of man
Those eyes will never stop
We now have put some background behind the image. The listener probably now has the same image but some feeling behind it. The eyes now seem to have an unmoving, unrelenting quality to them. Now it seems as though they will watch forever, which could be more powerful if the rhyme was better.
So, now that you are armed with this knowledge, set out to create three seperate images with seperate feelings and write two verses about each one. See which kind of image you are better at making, and what details you are able to convey. Try to make your image have a second meaning behind it. Connotation and denotation are always good. Once you've found an image you like, attach a story to it. Try writing the image from different perspectives. My one about the starts is written by an outsider but what if I wrote it as the stars? Or as man? Experiment and find the best image for you.
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Again, thanks!