I have recently bought a hair weft which is 3ft long - does anyone know if I can cut this or if I double this and then sew it?
:)

Weaving can be tricky. What you can do is measure the length of the weft where you want to put it and then cut it. Generally speaking from ear to ear is about the distance. Starting from the base of your neck measure the hair where you intend to put it and cut. The distance will grow as you work your way up your head or you can work from the top. However, yes it can be cut.