It is really important to choose the right interfacing for the fabric you are sewing. For example, if you are sewing a knit fabric, you should use a knit interfacing that is the correct weight for your fabric. Try to match the weight of the fabric to the weight of the interfacing. If it is a crisp fabric use a crisp interfacing, if the fabric is drapable, use a drapable interfacing and your choice should be just fine.

Always choose the best quality interfacing you can afford. If you choose a cheap interfacing, it may not fuse well and you will be very disappointed with the finished product, especially after you wash it.

Some fabrics can be interfaced with self fabric too. Sheer fabrics lend well to this technique because other interfacings show through.

High quality fusible interfacings are my preference for most garments. I generally use light or medium weight interfacings for most fabrics as well. If extra stability is needed on a piece, such as a waistband, I cut the interfacing to cover the entire piece & fuse it on, then when the waisitband is folded over it forms a double layer of interfacing.

To save time, I like to set aside all of the pieces that need interfacing. Then I cut a piece of fabric large enough to accommodate all of the pieces. Now cut a piece of interfacing just slightly smaller than the fabric, so it doesn't hang over the edge, and fuse the interfacing to the fabric. Once the interfacing is cool, I lay out all of the pieces and cut them out at the same time. The results are beautiful & my iron and ironing board stay clean too.