I use regular copy paper, a very small stitch and the PP technique I use means the sewing line gets creased twice so the paper comes out easily - even in the twisted log cabins as seen in my avatar which have 7 logs per a 6" block. I find it quite soothing to do in the evenings. I take out all the logs as I finish the block but leave the centre piece as it's labelled to identify the block. Like Amma says, if the fabric is dark then tiny bits left in will just dissolve in the washer. If it's light though, be sure to get every scrap out - I once saw a beautiful PP quilt made by a member here with cream fabric left with ink stains after she washed it - a crying shame literally. :cry: