Inspiration strikes out of nowhere. A piece of music can set it off or a passage from a book; what is seen or that which is experienced. The creative mind is triggered and something begins to take shape.
The thing created often is nothing like the original. This is because you were inspired to do something else. That which influenced you was merely the catalyst to get the creative juices flowing.
Those who copy from others are not inspired. At least, not by any creative impulse. Their motivation tends to be the love of filthy lucre.
Sometimes the energies flow freely, and the work is swiftly completed. Other times, what is desired lies just out of reach. Effort will be required to achieve what was truly envisioned.
Since ideas can come from anywhere, it is best to immerse yourself in whatever stimulates your creativity. Read that which interests you, watch whatever intrigues you, listen to anything that grabs your attention. Any of these ingredients can spark the imagination.
Once the fire is started, it must be fed. This thing lives off your energy, and will be extinguished by its lack. Feed your imagination and let it grow to become something truly wondrous to behold.