There are a million and one ways to make your own vent covers. There are also a million and one different designs that are already out there for you to purchase.
Below you will find two of the best materials for floor register vent covers. They are also the two that many home owners wouldn't even think about using. They are also, however two of the most popular now days as well.
This is becoming one of the most popular materials used when talking about a vent cover. This type of material of course depends on what type of material your actual vent is made out of. Being that it is magnetic, you will need a material that a magnet will actually stick too. With that being said, a plastic vent probably would not suit well with a magnetic cover.
Unheard of, or at lest un thought of probably. Most home owners would pose the question of the need to even have a cover if it is made out of mesh. However, a very taught and close together mesh makes a great cover for your register vent. This allows air to circulate through a tad bit, as well as keeping it covered at the same time.