Click [ Register or Signin to view external links. ] to go to the website that allows you
to do this.
Also, this only works with Generation games 4 & 5 (PKMN HGSS/DPP/BW).
Under the website banner, find where it says "Online Pokesav".
Click it and pick which generation you have.
All DS games non-BW are generation 4. Black and White are generation 5.
Select what pokemon you want, and you can edit its stats very in-depth.
I recommend activating PID, so it corrects your PKMN to be legit, such as mistakes on EV setting.
After you are done with those stats, before you sumbit the PKMN, manually edit your Nintendo WFC settings and make it so it doesn't grab the DNS server automatically.
When it lets you set a primary DNS, put 199.119.163.34 as it.
This allows you to connect to the private like GTS.
Also, make sure your DS is connect to the same network as the computer you're doing this on.
Once you are done, submit the PKMN.
Congratulations, go to the GTS in your game to receive your new PKMN!

There is also another way, but you cannot edit your pokemon's stats. Click [ Register or Signin to view external links. ] to go to Pokecheck.org. Once you are there, register. Once you are there, you can search any PKMN. Once you find one you want, you can put it in your download queue and you can download it by setting your primary DNS to 088.191.118.153 and connecting to the GTS. Note: Your DS and Computer need to be on the same network.

Have fun and press thanks if it made your day!