Football scoreboards come in a variety of designs. Buy one according to your budget and your needs. For example, you could get a simple board where you can write the score with chalk or pen. This should be big enough to be seen by everyone.
You could also find scoreboards with built-in numbers on cardboard. You simply flip with every goal to display the updated scores. It is like turning a page in your notebook. These are often placed on a tabletop and are great for schools or amateur clubs.
If you have a higher budget, then consider getting an electronic scoreboard. These would be great for night matches because the numbers will be easy to see. Aside from displaying the score, this may also show the period and a timer. Some will even show the number of timeouts left.
