Yep, pretty self explanatory.
You will need the following:
-A six or four pack of a beverage that comes in glass bottles (Non-Alcoholic would probably be best so your great aunt muriel who never drinks doesn't faint at the site of you giving her a gift in old Bud Light bottles and forever thinks of you as a heathen child.)
-A friend (or just yourself) to help you drink them all. Save all the caps, and gingerly take them off. Save the caddy it comes in.
-Pliers
Optional/Pick at least something from this list unless you just want to give them empty bottles.
-Red and Green hard candies
-hot cocoa
-Marshmallows
-Peppermint candy canes
-Any random goodie you can think of that would fit inside a glass bottle.
-Ribbon
-Mod podge
-Festive looking paper.
-Acetone nail polish remover and a rag (for removing any labels painted onto the bottles.

Step 1: Clean and Dry Your Bottles

For heavens sake PLEASE make sure your bottles are super clean and TOTALLY DRY before you put anything into them.
M&M's and water do not mix well and it will ruin your gift and make the recipient of it probably cry and it's all because you didn't wait for them to dry out.

Also, Did I mention you need to save the caps that you didn't do that weird bendy thing with your hands and shove them into the bottle after you drank them?
And the caddy too, You saved it, right?

And if you want to remove any painted on labels now is the time to do it. Douse a rag in some acetone nail polish remover, wrap it around the label and let it sit for 30 minutes to an hour.
Removes rag and wipe away label.
Clean it so it doesn't reek of a nail salon. Candy and nail salon fumes are probably not a very jolly mixture.

Double check again to make sure everything is clean and dry, then move on to the next step!

Step 2: Time to Add the Goodies!

Note: You may or may need to fashion a paper funnel that you taped around the neck of the bottle because you can't find your real one.
Insert candies. I chose for the six pack to add in red and green M&M's, you can find those two colors sold together in any store around December.
Or I suppose you could just buy waaaay more M&M's then needed and sort through them. But at that point you've touched all of them with your hands and gotten your dead skin cells and body oils all over the candy, I mean, unless you are giving these to an enemy you may not want to go that route.
Anywho, open the bags and insert the candies into the bottles, Don't be stingy and eat them all yourself, fill em' up to the top.

Alternately, you can buy some hot cocoa pouches, candy canes, and marshmallows, Add the powder first, fill it up to the bottom of the neck of the bottle, or just wherever you want. Then add your marshmallows in. If you are overly paraniod and fear them clumping together, or you prefer the jumbo ones, just place them in a cellophane baggie and tie it off on the side with the candy cane.
Take your ribbon and tie the candy cane around the neck of the bottle in a pretty and festive looking bow. You are a regular Martha Stewart now! Pat yourself on the back and get ready for some mildly tedious work in the next step.

Step 3: Time to Get the Lid Back On.

So, take your lid and with pliers go all around the edges and bend it in slightly, then pop it on your bottle, take your pliers and go around the edge of the lid while it's on the bottle and squeeze.
That is a pretty terrible explanation, but I have a video in the next step that will show what I mean.

Step 4: You Are Finished!!

Eat any left over candy and take your time decorating the bottles and caddy however you like.
If you need some more help and/or just want to watch me explain the dangers of inserting dry candy into a wet bottle and show how I made these in video form, Watch the embedded video below! :0D
Merry Festivus to all and to all a good day!