Best way to do a Watch Dogs Giveaway.

Anything but a puzzle...

CV of $30.01 or higher and a private link posted in a forum thread.

Only for people who have never won (plus some guideline like been a member for over 6 months, over 100 comments, etc)

1 hour giveaway, hidden in a random comment.

Hide the link on a webserver, visible only to those who hack in.

Do a giveaway open to everybody, no rules, no bullshit.

I would suggest a minimum of 60.00 CV, with the link posted in a forum thread, open for a few days.

Best way to do it? A giveaway with 7 billion copies so that everyone can win. ;)

Private link and send it only to me.

if you've got a webspace: maybe involve some javascript "hacking"
hidden RAR files in images
hidden urls in exif data
some ciphers
...

just look up zel's puzzle guide and combine whatever you like ;)

well - puzzle ofc! ;p