To fill nail holes in your walls where pictures once hung, mix up a couple of teaspoons of cornstarch and add water until it's a putty-like consistency. It dries relatively quickly and works like a charm.
By Oak-Trees
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An easy way to patch small holes in the wall is to use white toothpaste (not the gel type) and smooth. It can be painted over or covered with wallpaper. It can also be touched up with colored pens.
When you want/ need to cover up a nail hole on your wall, use white toothpaste. Put a little bit on the tip of your finger spread it smoothly over the nail hole. When it dries you can paint over it or leave as is.
I recently moved a picture in my dining room. There were nail holes left in the wall. We had guests coming for dinner.
If the nail hole is big enough, use a toothpick to fill it, break it off, sand lightly, and cover with the white toothpaste. Or you can use Elmer's white glue to cover the toothpick. Toothpaste may fall out but the glue will stay. Just make sure you wipe off the excess.