If you end up with a broken window, you want to get the window replaced as soon as you possibly can. However, if you aren't able to have the window immediately replaced, then you don't want to just leave it broken in the meantime. There are some things that you can do to temporarily fix the window. However, these fixes will not make the window safer or help maintain the temperature that you are trying to keep in the house. However, in a pinch, here are the things you can do for now.
Fix small cracks or holes in the glass
If you have a small crack in the window, or a small hole from something like a pellet from a pellet gun, then you can temporarily fix it to help somewhat with the draft and to keep insects from coming through the window. To do this, you want to take some clear shellac or something like clear nail polish. Place it in the crack or the hole. Allow the first bit to dry, and then continue adding more layers until the entire crack or hole has been completely sealed and is even with the rest of the window.
If the crack is a bit larger, then you can use clear glue to glue some clear plastic wrap inside of the crack. Then, you can build on top of the plastic wrap with your shellac or nail polish. Again, you want to build it up by adding more when one coat dries, until you have it even with the rest of the window's glass.
If you are going to be able to have the window repaired very soon, then you can even put clear packing tape on both sides of the window. However, know that this tape won't stay on long, especially if it is hot outside, very cold outside, or if it rains on the window. Plus, the window repair will be very noticeable when you go this route.
Fix a completely broken window
If you can't have the window replaced for a bit, then you can carefully remove the shards of glass from the frame and purchase the correct size of plexiglass from the local hardware store. Put the plexiglass in the frame until you can have the window professionally replaced.
If you can't get to the hardware store right now, you can take two sheets of plastic and tape them to both sides of the frame with clear packing tape. However, this is an undesirable repair job and should only be done for an extremely short period of time.
Call a window repair service for more information or assistance.