I found a link at Rebecca Brooks's Victorian Nonsense blog (a really great source of Victoria costuming ideas, particularly for those interested in Victorian childhood and culture) to Evange's patternless bloomers instructions.
This is a wonderfully simple way to convert a fairly small length of fabric into great poufy bloomers!
Rebecca made an alteration to Evange's original instructions that creates a little ruffle on the bottom edges of the bloomer legs.
Because you can never have too many details with Victorian costume, my version creates a larger ruffle, edged with lace.
Follow the original instructions. Make a narrow hem on the bottom of each leg. Add lace on the top. Then add a piece of satin ribbon on the outside of each leg bottom, as I show in the second photo -- it's about an inch above the lace, and the ribbon is 18mm (just over 5/8") wide. Sew narrowly along both sides of this, so you create a casing.
Then elasticize it as usual. You'll have a frillier, prettier pair of bloomers to wear with your Victorian or Lolita costume!