Sure you can put a down comforter inside a duvet cover no problem.
Can you put a duvet cover over a down comforter.
Basically take the comforter.
Start by taking a duvet cover and turning it inside out and lay it out on the bed with the open end down near the foot of the bed.
In fact it s always better to have a duvet cover and it s also more fun.
Then take the comforter itself and just spread it out on top of the cover.
To get the comforter inside the duvet cover simply open up the duvet cover and turn the whole thing inside out.
Some comforters also come with tabs but the majority do not.
Duvet covers are meant to be washed and will experience fabric shrinkage.
Put your duvet cover on the top of your bed and make sure the opening is at the foot of the bed.
Of course you can use a duvet cover even though your comforter does not have anything to attach it to but that is not very convenient.
So even if your duvet cover measures the same as your comforter it will likely shrink 3 5 and fit more snugly over your comforter.
Ok now here s the real trick.
Sure it will work you just have to watch that you pick a duvet cover that is not so light in color and fabric that the design shows through from the inner comforter.
Putting a duvet cover on your down comforter is much easier with 2 people although it can be done with just one person.
So to answer your first question.
It most likely contains cotton to be classed as down proof to keep fill inside.
Start at the top of the top end and just roll it over all the way down.
And again the cover is inside out.
Here are step by step instructions on how to complete this task.