Ideas will come into my mind and they don't go away until I write them down. Other times I write a phrase or word trying to convey the epiphany I had, only to read it later and say -- what the hell was I thinking? What frame of mind was I in? A few times I'll try to remember the thought I had acting like a "would-be" writer.
I read somewhere "would-be" writers seem to think collecting material for writing isn't necessary because they'll remember it. Maybe I will but many times--no. That's a would-be writer -- "I'll remember that..."
Sometimes I'll be reading and I'll remember what my creative writing teacher said in 6th grade. She said, read the paragraph and think about what the author attempted to disclose. Read, stop, and think. She was the best! Many times a sentence will grab me and I'll think about it. It will soak-in like a sponge; linseed oil to wood.
Choosing the right words for anything will take at the minimum, one draft, one edit and one pass-over. Also, the secret to choosing the right words are...
and don't forget it!