Want to plan my chapters; don't know how

I have a basic summary of how I want my story to go, but I'm having trouble abstracting it down further. Does anyone have advice on chapter composition, or could point me to where I could find information?

I was in the same situation, and what I did is start writing focused on reaching the next plot point.

Well, since you have a basic idea, what I recommend is to figure out certain major plot points you know you want to include. Then, once you've got those figured out and in the right order, start filling in the blanks.

I never really planned any of my stories before beyond a one or two sentence idea, and it shows. My current story is the first one where I've sat down and actually planned things out, so I'm a bit new to it as well.

^He said what I meant to far better than I did.

If you know where the story is going, i.e. major plot points, just start writing.

The chapter breaks will jump out at you naturally.

Planning out specific locations for chapter breaks seems a bit silly given there's a 99% chance you'll change a hundred things anyways.

First I start out with a basic outline, which usually consists of the largest plot points including the beginning, and possibly the end scenes. Then I start a chapter-by-chapter outline, where I usually split up the chapters into scenes and describe exactly what would happen in each scene. When I get about three chapters outlined, I start the writing process, and continue outlining and writing at the same time, usually trying to outline around three chapters ahead of the writing. Every once in a while, the writing process will take me in a completely different direction then the outline, so I would either have to redo the outline, or include additional chapters that I think are needed.

But the advice above is good as well, that in the end, it doesn't really matter how you outline or plan, because it's during the actual writing process and afterward where the decisions that are likely to end up in the final product are made. The outline is only there to guide and inspire, not to serve as a blueprint.