Need a mixed color fiber to match a layout, simply twist different colors of DMC floss together then glue along the entire length with either an acid-free glue stick or liquid glue.

use embroidery floss for stitching in layouts

To glue Fibers try placing liquid glue directly on the paper or where ever you are placing your fiber, let it sit for a few minutes, before placing the fiber on the glue. When it starts to dry it will get tacky, place your fibers on top, pressing gently. That way you don't get any runny mess, and the glue does not come through the fibers.

Look at your LSS they always place fiber on sale you might not need that many yard but go in with someone and get a few bundles. You never know you might start knitting.