How do you install elastic into clothing?

If there is a hollow hem through which you can thread the elastic, unpick the sewing to gain access to the tubular channel it forms.
. Make sure the elastic is doubled and has a total length a bit more than twice the length of the hem you are threading through. . Thread the elastic through a narrow safety pin to use that like a blunt needle, and ensure the elastic is doubled for the whole length. . Feed the safety pin into the opened channel in the hem and work it round the hem, so it pulls the doubled elastic with it.. . When the safety pin arrives back at the opening, and is pulled out again, it will have pulled the doubled elastic right round the hem. . Remove the safety pin from the elastic, perhaps by undoing it, or by cutting through the elastic. Either remove excess elastic to leave a single length inside the hem, or leave elastic doubled up (dependent on preferred strength of elastication). . Tie ends of elastic in a “running noose” (sometimes called a “slip knot”), put garment on carefully to avoid the ends of elastic coming undone. Draw the running noose tight enough to obtain the correct fit and degree of tension to maintain comfortable support.
. Lock off the running end of the elastic by tying it back around the loop in the noose. Cut off excess elastic from the ends (but not too short/close as to allow it to come undone while wearing or laundering), and feed knot into channel of hem.
. Re-sew hem to close the opening you made at the beginning.

– Best wishes - Majikthise.