I have a "now", "soon", and "later" section in my TODO list.
"Now" grows and shrinks, but never gets out of control. Things sometimes move from "now" to "soon" or "later." I am constantly working off of this list.
The "soon" section varies. Often, things get pulled into "now", when they become time sensitive. Some things stick around long enough and it becomes clear they don't need to get done soon, despite of what I thought. These move to the "later" list.
The "later" list is interesting. Most of the time time, I don't touch these things. But occasionally, I look through it, and realize I am in the mood to do one of them, and then I work on it. Or the circumstances align and the situation is just perfect to get one of those items done. Occasionally, I go through it, and find things on there that are no longer relevant, and I remove them. For other things, I put them into various "fanciful idea" lists which are noncommittal, don't weigh me down, and could serve as inspiration if a need arises.