I received some lovely replies that a tutorial would be appreciated for my Kid's Duffel, so here goes:
Skill Level - BeginnerItems Needed -
Fabric - 1 1/3 yard - home decor weight or canvas will work best for this
Cotton Cording - 1 yard
Cotton Webbing - 2/3 yard plus more if you want to add an embroidered tag
Cut Fabric - I traced a dinner plate to get my base, which is a 10.5" diameter. I then measured the circumference of that to get the width of my fabric (plus 1/2" seam allowance), which totalled 34". I cut the fabric to length from the fold at 24".
Sew round to width with RST - Start 1/2" from the edge, and you should finish up with about 1/2" remaining. Stay stitch at beginning and end of seam.
Repeat on opposite end - you should now have what resembles a really long duffel bag.
Sew long side - with RST, sew long side together leaving ~ a 4" opening beginning about an inch away from the fold. This will be the opening for turning the duffel right-side out, as well as the area we will make the casing for the drawstring.
Turn right-side out - reach in and turn the bag right side out. I didn't find I needed to clip the curves at the base because they were gentle enough, and the seam allowance seamed to stand up in the bag nicely.
Push lining inside - use the fold as the top edge, placing the 4" opening on the outside of the bag.
Sew top seam - for drawstring casing right at the top of the opening.
Thread drawstring - around the interior of the bag. Just grab an end and push it around. Tie the ends together. Work the drawstring up towards the seam.
Sew bottom seam - for drawstring casing about 1" below the top seam. Try to get the bag to lay as flat as you can around the drawstring, and keep working the drawstring to lie close to the completed seam as you sew.
Sew opening closed - with a top stitch close to the edge. This seam will be mostly covered by the carrying strap, so it's okay if it shows. If you're super persnickity about the details, you could stitch this by hand with a hidden stitch.
Sew strap top - just below the bottom seam of the drawstring casing. Double it over so the raw edge is underneath. I folded under 1.25" as this was the width of my cotton webbing. Sew on using an X and box pattern to ensure it's nice and secure.
Sew strap bottom - 6" from the bottom of the bag. Again, turn under the raw edge and sew securely with X and box stitching.
Add a custom embroidered tag to the top just below the drawstring on the opposite side as the strap if you desire.
Enjoy! I'd love to see your versions if you make one. Bags made using this tutorial are for personal use only, please!