Da questo blog il tutorial per questi semplici e pratici sacchettini:

To start, you'll need about a 1/2 yard of fabric, folded and about a 36" piece of twill tape or ribbon (plus, thread, scissors and...a sewing machine...duh.). I'm using a lightweight linen here. I've made a simple pattern with a 12" x 18" piece of posterboard. Place the posterboard directly on the fabric with one edge on the fold.

Trace pattern directly onto fabric, and then cut out. You'll end up with a long rectangle of fabric when open.

If you are using a plain fabric (like I am here), you can easily embellish the bag later with embroidery, stencils, patchwork or little die-cut pieces of fabric. I think I'll add some fun die-cut fabric pieces. I found some simple shapes online and printed them out to make a little pattern, and then cut them out of some fun fabric.

(Not shown: I also used the die-cut patterns to cut out a piece of double-sided interfacing to help adhere the die-cuts to the linen later.) Put these aside for now.

Next, take your main fabric, open it, and with the wrong side facing you, press the top 4 inches of the sides in. That's not articulated very well, but check out the photo above and below, and do like that! You don't have to measure with this project, just eyeball it.

Do this on all four corners/sides. Then, press down the two top edge pieces about 2 inches from the top. You could serge this if you want, I did not.

Next, sew this piece down about 1/4" from the cut edge.

Then, using your sewing machine guide, sew across again with a 3/4" seam allowance. By doing this, you are creating a little tube for the drawstring.

Next, remember your cute embellishment? Now is the time to attach it. If you are using a die-cut piece of fabric, first adhere it to the right side of the fabric with lightweight double-sided fusible interfacing.

You can then embellish it further with embroidery - I whipstitched around the bra & bikini shown above (but forgot to take a picture of it! sorry!).

Then, turn the piece wrong side out, matching up the top pieces, and begin stitching the sides together below the last horizontal stitch line. You can start at the 1/4" seam allowance guide on your machine, because that turned in portion at the top will end, and you will continue at 1/2" seam allowance down the side of the bag. *Just remember not to start at the very, tippy top of the bag or your won't be able to insert your drawstring!

If you'd like, you can clip the bottom corner of the bag. Then turn it right-side out and press.

Take your twill tape or a piece of ribbon and attach a safety pin...

insert it into the second opening at the top and pull it through to the end. Then, insert it into the other side and continue pulling it through.

Make a little knot at the end so that little guy doesn't go anywhere...

Cinch it tight, and you are done!

Oh, look. Now I have three new utility bags! A lingerie bag, a shoe bag, and (*slaps forehead*) a knitting project bag!

I know which one I'll be using!