Or 2. You can add the beads as you go. It takes less prep time, but really slows down the knitting time. But you don't have to guess how many beads you need (or count them if you know how many you need--I mean counting is relatively easy but beaded projects quickly get into the hundreds of beads needed and that is just tedious) and it is easier on the working yarn.
I am working on a little something that required beads and the instructions called for adding the beads as you went. The pattern suggested using a tiny crochet hook. I have heard this before and have a hard time picturing a crochet hook so small it would fit through a tiny bead. I know they exist or people wouldn't be talking about them all the time, but I certainly do not have one.
So I made my own solution. I took some very light weight and flexible wire I have for beading. I cut a piece about 6 inches and bent it back on itself like a V. At first I used it with the ends even, but it's much easier if one end is longer than the other.
(I know, sounds tedious, right? It's knitting--get used to it. You either like it or you don't.)