Improving your keeper rate is desirable, but it also usually plots out your growth as a photographer; the higher your skill, the better your keeper rate. However, there are tips and tricks that are developed for the sole purpose of improving your keeper rate regardless of skill.
If you've ever been on a long trip where you aren't able to throw your images on your laptop or PC as you go, you will know what your keeper rate is like. The same is true if you conduct a lot of long shoots like weddings, but for me, it's trips that really show me how attuned my eye is for an image at that time. While improving at photography will improve your keeper rate, there are other tricks too. In this video, James Popsys goes through some tips he uses to ensure he comes away with as many images as possible.
Rather than discuss one of the tips in this video, I'll offer my own. One method I have liked to use for a number of years is this: when I see an image I can imagine will be good, I create it exactly how I saw it in my mind's eye. Then, I force myself to take the same image in a different way. So, for example, I might change orientation from landscape to portrait, I might change my perspective on the scene by getting higher, lower, closer, or further away, and so on. Even if the shot that comes from this exercise isn't good, it will regularly give me an idea for another shot.
How do you maintain a high keeper rate?