Eighteenth-century tailors had an interesting way of attaching buttons. Clothing was built to last. Buttons sewn on with thread are apt to fall off. Eventually, the cloth will rip. Besides--what if you wanted to change your buttons?
Below the four buttons in the picture are two helpful tools: a small bone awl and a glass rod. The trick is to poke holes in the cloth without damaging the threads. Start small and gradually enlarge the openings till the button shanks fit.
Using a large needle, thread 1/4" linen tape through the button shanks. Cut the tape just slightly longer than the space between the buttons (leather thong and cord was also used.) The tape is then stitched to the interfacing. Let's see those *&^%$ buttons fall off now.