Start by cutting your selvages with your preferred method as listed above.
Separate them into piles by color and/or pattern.
Press all strips well on both sides with the iron on steam.
Trim the raw ends and any frays that might be present.
For method #1
Set your sewing machine to a zig zag stitch or a decorative stitch of your choice.
Place two strips of selvage on the plate of your sewing machine, side by side. Make sure the needle catches both strips when sewing.
Sew the strips together.
Continue adding the next rows in the same manner.
When finished sewing all strips, trim the uneven strips (they might not be all of the same size). You can add these to the new fabric if they're long enough.
Press the fabric well and use in a new project.
For method #2
Press the strip of fabric well and turn it wrong side up.
Place the double sided fusible fleece over the fabric.
Top the fleece with the selvage strips, side by side.
Start fusing the selvages to the fabric one by one until all strips are attached to the fabric.
You can add a zig zag or a decorative stitch to the edges where selvages meet or you can quilt the entire panel with your favorite quilting method. I advise free motion quilting as it will catch more of the selvages, create a more interesting panel and gives the strips more stability.
Press the entire piece well with steam setting on your iron.