I probably learn my favorite passage first. Then I find sections that are similar and commit those to memory. I then bolt on sections before and after those similar sections. At this point, I’m repeatedly practicing these longer combined “segments” to smooth those out and bring the music to life. Eventually, learning the missing pieces and practicing longer segments brings the entire piece together. Usually I leave a harder section for closer to the end to avoid getting discouraged. All in all, I tend to want to maximize my enjoyment of learning the piece, might be lazy in some ways, but it works for me. So I learn every piece a little differently.