Keeping track of students' reading can be an organizational nightmare. I first started by using notebook paper and filing it in a binder, but that only gave me a day at a time. I found that a sheet with multiple entries allowed me to see patterns in reading and work on strategies. I still keep these in binders, but now when I open a student's conference record, I am able to gain a better understanding of their reading progress.
For classroom use, I print several of these per student, and place them in a large classroom binder with tabs for each student.