When you are beading, you need to use the thread that will accommodate the correct bead. If you have a heavy large hole you would be well suited to use c-Ion threat, number 18 upholstery thread or wire. Wire is the most appropriate for heavier beads. The size of beading needle you use is also important. Usually, a size 10 beading needle fits through many of the bead sizes that you will use.
Another good way for beginner to work with heavier thread is to use a big eye needle. The eye is actually in the center of the needle so at either end it can be used as the eye. Just open it in the center, put the thread through it, cut the length you want and you can then begin beading.
If you are working with lighter weight beads, a lighter thread is used. One of the preferred stringing materials is called Nymo, and it needs to be waxed or conditioned before you use it. Conditioning gives the thread strength and bulk and it is less likely to tangle or fray. You will need to cut the length you need and pull it across and bees wax for example Thread Heaven.
A good way to look at beading is that you are bringing the needle to the bead instead of bringing the bead to the needle. You are less likely to drop beads and can line them up on your working surface ahead of time so you will see how they will look once they are all on the thread.
Pearl knotting is a great technique to develop when beading. In the beginning you first take the bead and string it all the way to the end of the thread. Then you loop it back through the thread to make a large not, then you use a t-pin to bring it all the way to the bead before you pull the thread to sense the knot closed. When you pull the thread, no matter what type you are using, never pull it too tightly or you may stretch or break your thread and then you will have lost all your beads and have to begin over again.
If you are teaching beading, a good way for them to get used to it is to first use pipe cleaners for stringing your beads. This way they are not prone to fall off if a student is feeling awkward.