Instead of sewing a basting stitch (or a pair of basting stitches) you adjust your machine to a wide zig zag stitch. Grab a roll of lightweight fishing line and tie a big honking knot in the end. I mean big knot. If that pulls out, you basically have to start over. Lay your fabric out on the machine getting ready to sew. Now slip the fishing line under the machine foot, lining it up along the seam line and letting the knot lay several inches off the back of the fabric. Now keep the fishing line centered in the foot so the line is centered under the zig zag stitch. (As shown in the above photo.) Sew the full length of the fabric. Cut the fishing line so you have about 6-12" of excess line at the end.
Here's what it looks like sewn. Now pull the knot end out a few inches, just a few though. Go back to the other end and pull on the fishing line while sliding the fabric the opposite way. Your fabric will gather faster and easier than it ever has before. It's awesome and you will always keep fishing line around your sewing machine from here on out.
If you are planning on making the ruffle bag or the fat quarter ruffle bag couching over fishing line will save your sanity. If you are sewing tulle skirts for little girl dresses, this will save you from swearing like a sailor (also, when sewing tulle use a round nose needle intended for knits. I swear it makes a huge difference.)
And now you can actually have fun gathering fabric. Good luck with your sewing.