Well...let's break it down...
- Standard practice is to leave anywhere from 4 to 8 inches as a tail
- I, personally, think leaving 8 inches is just wasting your yarn. I generally leave 4 inches.
- Shortly I will show you how to deal with a super short end. So, technically, nothing is too short to weave it in. BUT, if you want the end to be easy to work with and stay in place, I wouldn't leave less than 2 inches and only in the instances when it benefits you to do so. For example, if you are running low on yarn and to preserve as much as possible, you can get by with 2 inches.
- You can use a tapestry needle or a crochet hook to weave in ends. I find that things work best with a tapestry needle.
My favorite tapestry needles are these gold-colored ones from Clover. They have a bend at the end that is great for moving around your work and the eye is a good size for lace weight to bulky. You can usually get a set of two for about $3.00.
If you have a very short end, you can pre-load the needle. This means that you put the needle through the locations where you want to hide the end. See in the above photo that the end is not yet put into the eye of the needle.
After you have the needle loaded up, thread the tail into the eye and pull the needle the rest of the way through the locations where the end will be hidden. Ta da! Short end is woven into the work.