If you are wearing wefted hair extensions, it is always a good idea to seal your wefts. the sturdiness of hair wefts differ from one company to another but in general, and type of weft that gets cut will shed a little bit. Over time with brushing and other sorts of manipulation will cause you hair extensions wefts to shed, so sealing is a great way of prolonging the life of your human hair wefts.
Sealing your hair extensions is really easy. All you need is a fabric sealer or a weft sealer.
Here is a great YouTube tutorial on sealing wefts: