I usually try an author with his most popular works and if I like him or her, I read everything he or she writes. Sometimes it is more difficult because I have a title in French or one in English and for the same work they are completely different.
Of course the best way to remember is to savor what I read, to stop and reflect if the work requires it. I did at some point take written notes but mental ones are better. Now I mark pages on the reader. If I come across a book with Marks, it's been read.
An other way is to format for the reader only if you plan to read the book. That way if you see in your collection a book that was fomated for the reader, (you know 16pt text!) chances are you read or tried to read it. Some books are boring or offensive to intelligence.
And best of all... a reading plan. Mine is ready for the next 3 months. Right now I'm reading Asimov's 14 foundation series.