I'm a tool gal. I believe that the right tools make the job easier, so I tend to invest in the right tools. This is the set of tools that I think of as the "right" tools for sewing bras and lingerie. It includes...
Clover Silk Pins (some fabrics are hard to pin, these are much easier. The easiest are the Bohin Ultra-fine pins).
Mini Wonder Clips - you can use Wonder Clips to avoid having to pin at all! They can also be used to mark match points and such.
A disappearing ink marker - you don't really want to cut notches or clips in these tiny seam allowances. Marking with a marker is much easier.
Easy Check Tape Measure - If you've ever tried to manage all the parts of measuring yourself and had to repeat several times, then you'll love the Easy Check. You drape it around yourself, clip it closed, adjust to the perfect spot and tightness and then unclip. Your measurement is captured right there on the slider!
Sewer's Aid - you might know this product as a thread conditioner, but it is also the very best thing ever to get wires into channeling! It can be tricky to push the wire all the way through, and this makes it easy peasy!
Needles - Some lingerie fabrics can be tricky to sew, so having a variety makes a big difference. This variety includes a package of Schmetz Microtex 80/12 ( a workhorse), Bohin Jersey assortment (magic needles that work when nothing else does), and a variety of sizes and types so that you can discover your own best needle for your fabric and your machine. The Sewability kit also includes a piece of Tearaway stabilizer, which is perfect for starting seams.