Re-casting on

What is the best method to cast on a current project? I had to cast off to leave an opening and now need to re-cast on.

Thank you!

i like to use a knitted or cable cast on mid-project i have heard people mention the backward loop aswell (although i could be wrong)

Yes, you could use any of those, though the backward loop tends to be very loose and leave extra yarn when you knit into it on the follow row. So I prefer knitted or cable CO.