We just uploaded a new video tutorial showing you how to make a wireless bra using Jalie 3131 - Bra and Camisole sewing pattern. In the video, you can steps from A to Z and Jeanne shows both the regular and nursing clips (on the same bra).
Here are links to SewSassy, where you can find all the notions used in the video:
Sliders and Rings
Hook and Eye Closures
Strapping and Finishing (plush) Elastic
If you would like to insert bra cups, simply cut an extra pair of cup linings. Before assembling the bra, baste a first lining to the cups. Then, cut across the top of the other lining (this will create an opening between the two linings), pin and baste it so the cup+lining.