Your thoughts/emotions are the starting point.
You come up with an idea, you have a feeling you want to express, you see a scene you want to capture, a color or texture that takes your fancy, you have a 'what-if?' moment.
Now problem-solving comes into play.
How do I capture that light? How do I blend that unique color? How can I get my brain to tell my hand how to express what I see and how I feel?
And now it's about technique.
And technique is about practice, it's about honing skills and about trial-and-error and repetition. There are no short cuts. Mixing the exact color, capturing a particular expression, translating motion to a static image-- all these take the exercise of skill, skill that's constantly upgraded and expanded by doing the artistic task over and over, of practicing all the steps that lead up to the final smooth application of the technique that solves the problem, that captures the moment-- in the sketch, the necklace, the lyric, the collage, the watercolor, the embroidery, the symphony.
Every masterpiece-- no matter how small-- starts with a problem that is solved with innovative thought, combined with a gigantic leap of faith and then completed with skill and technique.