Decide first what you want to compose- whether using an existing type or genre of piece or creating your own. In other words, have a concept first- and then actually composing will be easier.
For example, you might want to create a symphony- in which case you'd probably want to use symphonic form and assign roles to different groupings of instruments for different sections, or tweak and change this concept/form a little.
Or you might decide you want to create a piece where every instrument is playing different rhythms at the same time; then you just have to decide for how long and what those rhythms are.
Having a clear concept will tell you how to place instruments and compose material to fulfill it. It's much easier than just sitting down and writing without any prior plan, although you can also try to do that- you can improvise a piano piece and then arrange it or orchestrate it for your ensemble. But then even that is a concept.
|