To hit your seed requires two elements; you need to hit A on the continue screen at exactly the right time and date (to the nearest second), and you need to get the right delay.
Getting the right time and date is pretty easy; simply set your DS calender and clock, synchronising the clock with either a timer (such as emloop), a second clock, a watch, a stopwatch, the clock on your computer, whatever. It's then pretty simple to use this so that you press A at the right time.
The harder part is hitting your delay. The delay is a quick countdown of about 60 per second that occurs from turning the game on until you press A on the continue screen. Usually, you'll be soft resetting (hold L, R, Start and Select) to restart the game, so the delay counts from when you soft reset until you enter the game.
The best way of hitting your delay is to use a timer programme. Here's a link to emloop: http://pokem.client.jp/emloop.htm
and here's a guide for how to use it:
http://www.smogon.com/forums/showpost.php?p=1907765&postcount=7
(Though, there are slightly better ways to use it...)
101 Raikou :106) though the guide says thats only for European versions,or am i wrong...i dont know what to do, does anyone have any idea whats wrong?