Sewing Stretch Fabrics

Dear users, dear authors,
What should you keep in mind when sewing with stretch fabrics?

For stretchy fabrics like jersey or fabrics with elastane content, you should have a needle in the machine that has a rounded needle tip, i.e., a jersey stretch or Microtex needle. This rounded tip prevents the fabric from getting holes while sewing, or worse, from getting runs—both unsightly. 
Then a walking foot is recommended; there are sewing machines where it is already built in, as with Pfaff machines. I wouldn’t want to be without this IDT system anymore. But there are also machines where you can buy it separately. For anyone who doesn’t have or want either, there is another very inexpensive option: place sandwich paper under the presser foot while sewing; that also helps prevent unwanted waviness in the seam on elastic fabrics. When unpicking, if it should ever be necessary, extreme caution is required, because all elastic fabrics, including wool fabrics, are very difficult to unpick; if you’re not careful, you can quickly end up with holes in your sewing project.

• When cutting the fabric, pay close attention to the grainline and the direction of stretch; otherwise, the garment will warp when worn or washed.
• Avoid accidentally stretching or pulling the fabric while cutting and sewing, as this will cause ripples later on.
  The exception is cuffs, which must be stretched when sewn on.
• Minor ripples can be ironed out with plenty of steam.