Need help with 2 strand knitting

I will be working on a new pattern that states I have to double strand using the same pound of yarn that I will be working on.

So do I use both ends of the yarn and if I do, how do I handle snags?

Any info will be greatly appreciated.

When I’ve done it, I’ve used both yarn ends. The yarn from the inside of the skein inevitably tangles, but those are easily sorted.