Read the entry rules carefully. You may be disqualified if you don’t follow them exactly.

Be cautious of the wording of sweepstakes letters, which often give you the impression that you’ve already won something, and that you only have to send in a “donation” to collect. Remember,you don’t have to buy or pay anything to enter a sweepstakes. Don’t put personal information such as your Social Security Number on an entry form. If the entry form requests your income, marital status, or other sensitive information, think carefully about whether you want to provide it.
Sweepstakes often identify “pre-selected winner(s)”. This usually means that each “winner” has been randomly selected by a computer and assigned a number, with one or more persons receiving designated prize(s). If the sweepstakes promotion states you are a “pre-selected winner,” you may be eligible only if you respond to the sweepstakes, and you may not win the prize that you want.