Competitions on line

[Jennykenny]

There must be hundreds of thousands of entries for competitions online. Has anyone any tips on shortening the odds????

[VHG]

Many of these online competitions are just a way of getting you to give them your email address so they can send you junk mail.

[factor-fiction]

For any given competition, other than having several accounts under different user names/email addresses and using all of them, no I don't see a way of shortening the odds.
The only other way is to focus on those competitions that get fewer entries