How many courts are available?
This number may not necessarily be all the Club courts, because they may be other activities on like coaching, leagues or social nights.
How long will the tournament be?
What type of draw will you use?
Although the ideal type of draw is one that provides more than one match per player, like the round robin or compass draw, you may have to use a knock out draw if the number of entries is high, the number of courts available is low or you are running it in only 2 days. The ITF has produced a very good book called ITF Competition Formats Manual (1999 Crespo and Miley) with a wealth of information on tournament formats and types of draws. You will also find some useful information in the ITF Play & Stay website.
What format will the matches be?
If time and court availability are a problem it may be better to have third set champion tie-break or shorter sets.
How much help will you need?
If you are running a junior tournament you will need much more than if you are running a senior one.