I'm a minimalist when it comes to a quilt journal. I keep digital pictures online, and I keep a spreadsheet with the date finished, a small description (which includes pattern name if known), date completed, quilt dimensions, whether it's been in a quilt show, whether it has a sleeve and label, and disposition of the quilt. I wish I had kept track of the batting used. There are others who keep pictures of the quilt-making process, names of the fabrics used, price of the fabrics, problems encountered, just about anything you can think of.