I generally fill a sink with warm water, not too hot and leave the piece to soak for anything from 15 minutes to half an hour depending what else I'm busy with. I do swish it around in the water a couple of times and I'll only add a dye catcher sheet if I'm concerned about some of the fabrics bleeding. I don't need to use them to catch the ink in the pens. I pre-wash most fabrics but sometimes those reds bleed regardless.
You can see how the water has changed colour from the ink,it's suspended in the water and has never affected my fabrics or run onto them. They are acid free and non toxic. Sometimes I steam press my applique with a hot iron and that doesn't even affect how effectively it washes out. I have left ink in a quilt for a couple of years and it still washes out beautifully. For more information, see this post.
I rinse a couple of times in cold water and then squeeze, not wring the excess out. I then flatten it out on a towel as in the photo above, roll it up inside the towel to get more water out and leave it flat to dry.
Once it's dry, I'll double a towel on the ironing board and give it a good press with steam. The soft surface stops the applique from pressing too flat and it helps to get the wrinkles out between the applique shapes.
It's hard to get a good photo of long borders but you get the idea. I've left quite a bit of negative space to fit some nice quilting in and I also didn't want the border to be too busy looking. There's still more to do to turn the corners at each end but I can't do that until later when sides are joined.
I finished another border for the Aunty Green quilt and thought I'd show you more close up photos so you can see the fabrics. The above is the center section.
The right side
Until next time, happy stitching, Janet