How exactly does one go about tieing a cherry stem into a knot? I have a 4lb box in the fridge and plenty of time to practice, so any suggestion that you can provide is welcome.
Well, first, you have to chew on the stem to soften it up enough to manipulate into a knot with your tongue and teeth.
After that, I don’t really think I can talk you through the knot tying. That’s something you really have to learn on your own.
Of course, I say that and somebody is bound to come in here with step-by-step tongue to stem instructions or a cite with illustrations.
Good luck.
step 1 (to be done out of sight) take a stem, tie it into a knot and hide it under your tongue.
Step 2 - In plain view, put a stem into your mouth, pretend you are having a hard time tying it into a knot. After a while you produce one tied into a knot. Tada!
The hardest part is getting the knot tight enough to be a real knot.
Anyways…
How to Tie a Cherry Stem Into a Knot With Your Tongue.
Take one cherry. While staring deeply into your SO’s eyes, place the cherry, stem side out, halfway into your mouth. Slowly suck the cherry inside. Bonus points if you can do this without laughing.
Separate cherry, pit, and stem with your teeth and tongue. This will let you know if you have agility with your tongue to attempt the next part.
After spitting out the pit (I know of no delicate, seductive ways to do this, though. Just don’t propell it across the room), swallow the cherry. Now you just have the stem.
Manouvre the stem so it lies across your mouth, molar to molar. Then, when you push in the middle with your tongue, it starts to bend in a arc. This is the tricky part, and what requires the practice. You then have to keep bending it to complete the circle, and tuck one end of the stem into the circle with your tongue. Sometimes it helps to kinda hold the stem circle gently in your teeth (about the middle of it), while attempting the tuck.
When removing the cherry stem, subtly grab one end with your teeth and grab the other end with your fingers, tightening the knot as you remove it. Also while staring deep into the SO’s eyes. More bonus points for sucking your fingers as you do this.
The first few times you do this, you will look a lot like a cow chewing cud, but shortly, you will be able to tie double knots without looking like you’re doing anything.
Preview is your friend. I was just about to invoke Arden Ranger plus a couple others like maybeHamadryad or evilbeth to help.
This is as close as I can get to step-by-step instructions, unfortunately I have no digital camera to illustrate each step, and no cites.
Lemme know if that helps…
I agree 100% with the above instructions, but would like to add that this is much easier with a maraschino cherry - the stem is generally softer, and and there’s no pit. 
Use a maraschino stem, and you just have to visualize what you’re doing with your tongue and teeth to the stem.
I can do it, but nothing like an old GF used to…she could tie ten stems in 7 seconds, one right after the other.