I sort mine according to makers....all quilting quickly tog and then MQ Blocks...etc

I have mine by color. I remember each book by the color and picture on the cover before I remember the name of it. I know the book I want is blue, I go to the blue books. I've been downsizing my books too. Some I haven't looked at in years so why keep them. I give them to my quilting friends. If I ever find that I have to have see it I can borrow it back. Let them store it. LOL I went to two bookshelves full to one small bookshelf. I haven't missed a one.

I do mine by theme. Christmas, easy, crazy quilting,etc.

Pretty much what I've done with exception of afew authors...like EB, F&P, all others as above.
actually thinking now, some of those need to be thinned out....haven't opened a few in several years....hmmm.....

I have had multiple hobbies over the years, all with books. I store by topic. Depending on how many I have undet each topic, I may sub-group by subject (children, adults, household) etc.

I haven't taken the time to organize them. I am making quilts to donate using scraps and usually just make them up. I seldom use my books.

Some are by autho rfor example Nancy Zeman. Eleanor Burns, The rest by type applique,or piecing. Diane C.

These are the TOPICS I sort by (about 3 shelves worth): just block patterns, applique, art quilts, quilt history, modern quilts, color theory, how to books (e.g., helpful charts, quilt borders, machine quilting and other technique books), general pattern books (grouped by author if more than one, but not alphabetical), and I seem to have several books on just one quilt design such as lone star, monkey wrench, storm at sea, bargello, log cabin, etc. and those all get grouped together in that section. This method at least helps me know which end of the bookcase to start searching for the book I'm looking for! :p

i sort mine by subject matter &/or author ..ie -barbara brackman, applique, designing/drafting and block encyclopedias

my bigger problem is not the books, but all the pages I have either printed or taken out of magazines. I finally took a day and organized (most) into a file drawer by name of pattern (although sometimes I renamed them with a name I would be more likely to think of!). I have 2 file cabinets under a large piece of wood that I use as an additional desk. I am currently in the process of scanning most into my desktop background. This was a tip I saw on this board. This way they are always being seen and I keep them fresh in my head. If you do a few at a time, it isn't as daunting as it seems.