Bulky numbers can be part of the birthday decoration. They look good on New Years too. Such figures can be made from polystyrene, penofol and other materials that are easy to process and keep their shape well. If nothing like this is at hand, paper will do, but there should be a lot of it.
Make blanks
Old newspapers or printer paper are fine for making small numbers. Large numbers are best made from paper wallpaper. For a couple of numbers, half a roll is enough. You also need PVA glue or starch paste, a sharp knife, a piece of thick cardboard for a template, water-based paint, foil or colored paper, gouache.
Make a template out of cardboard. This is just the right number in full size. If you want it to have a cut pattern, cut out the pattern on the template as well. Cut out blanks from the wallpaper according to the pattern. There must be at least twenty of them. If your number will be without slots, simply circle the template twenty times and cut out each piece. For a number with slots, make half of the blanks solid, and half with a slotted pattern.
Digit making
Lay out one piece. Lubricate it thoroughly with glue. Lay down the second piece carefully, aligning all the edges. Let the layers dry, then stick on the next sheet, fourth, fifth, etc. If the number is solid, just glue all the blanks. Align the edges with fine sandpaper. Cover the number with water-based paint, and paint on top with gouache. You can coat your creation with acrylic varnish or even hairspray.
To make a number with a slotted pattern, glue the halves first - the lower one without a pattern, the upper one with a pattern. Prime and paint the upper part. On the half that will be at the bottom, glue foil or colored paper. Glue the slotted layer. A floral or geometric ornament will look good on such numbers. You can also make decoration in a folk style - for example, oriental.
Corrugated paper numbers
For such numbers, you will need packing cardboard and corrugated paper. The thicker the cardboard, the more impressive the number or letter will look. Draw the desired number directly on the cardboard (best of all with a ballpoint pen or marker), cut out. Remove the most visible irregularities around the edges. In this case, you will not need perfectly straight lines, the contours will be hidden by a fringe made of corrugated paper.
Cut the paper into strips. Their length should be about one and a half times the width of the letter, so that the strip can cover the sides of the workpiece and there would still be an allowance for gluing it to the back side. Use a comb to cut each strip. Start gluing the strips from the bottom. Glue each next strip so that the fringe covers the strip glued to the cardboard. It is better to make the topmost strip somewhat wider than the others so that you can bend it to the back side.
Such figures are made for the panel. If the decoration will stand on the table, it is necessary to wrap all parts of the letter with fringe, and make a stand at the bottom (for example, from thick cardboard).