Turn the sweater inside out
Gently pull the fabric around the snag to redistribute the tension
Use a crochet hook, needle, or latch hook to pull the loose thread to the inside
If the pull is small, massage the fibers back into place with your fingers
For wool or knit sweaters, lightly steam the area and reshape it
Trim only a tiny frayed end if necessary, without cutting the main yarn
Secure the thread on the inside with a small knot if it is loose enough
Use a fabric shaver to smooth any raised fuzz around the pull
Lay the sweater flat and let it dry completely
Take the sweater to a tailor or dry cleaner if the pull is large or the knit is damaged