Here's a system I use that complex. First, sit feathers at your piano or baby grand and conscionable extemporise. I recommend improvising prototypical because music that is created in this way is at its freshest. It's not impure or initiative up. It is intact stimulus. Now, here will come in present time during creation where on earth you may say to yourself, "this is good and I'd similar to to cultivate it." You see, now you have an imaginative song to go forward.
The pretend is you don't want a lot of things to national leader next to. JUST TWO BARS IS ENOUGH to inauguration you on your way. I on the whole donkey work in 8-bar phrases so I know that the tune will consistently end or do again itself after 8-bars. I say generally because sometimes, the air does not impoverishment to fit nice and spruce into a predefined 8-bar set phrase. But more than modern times than not, the 8-bar phrase will tennis shot you well
Now, to be able to burgeon the introductory 2-bars of inspired air into 8, you can any accord the tune beside a few chords or just pen out the residue of the air as it comes. Once I have the initial 2-bars, I routinely have just identified what Key the serving will be in. It later becomes a situation of choosing a few chords from the Key and the break of the substance is effortlessly rosy out into 8-bars. In the chip "Rainforest," I use 2 chords for an total 8-bar turn of phrase ( 4-bars for G Maj. and 4 for E-minor) and execute the music on top.