Instructions
Find and capture a Budew. You can find this grass-type Pokémon in Eterna Forest or on Routes 204 and 212. Budew will know "Absorb," a move that earns smart points in smart contests.
Use the Budew in battle until it reaches level 13. At this point, it will learn "Mega-Drain," another smart move.
Raise your Budew's happiness level by taking it for walks, letting Daisy groom it, or giving it a Soothe Bell. When the Budew is very happy, level it up during daytime hours to evolve it into a Roselia.
Use a Shiny Stone on Roselia. You can find a Shiny Stone on Iron Island or Route 228. This stone will force Roselia to evolve into Roserade.
Speak with the Pokémon Fan Club President in Hearthome City. He will give you a Poffin Case.
Gather a few berries of the following types: Rawst, Lum, Nanab, Aguav, Haban and Jaboca. You will need these berries to make Bitter Poffins. Berries are found scattered about the environment.
Travel to the Poffin House in Hearthome City. Speak with the person in the house to begin the Poffin-making minigame. You will need to stir the Poffin mix in different directions without overflowing or burning.
Make the best Poffins you can make. If you are able to make Poffins quickly without burning or overflowing, they will be more effective. Practice making Poffins until you are excellent at it.
Feed Bitter Poffins to your Roserade. These Poffins will increase the intelligence of the Pokémon.
Enter the Ultra Smart contest with your Roserade. The Bitter Poffins will boost her intelligence, and you can perform smart moves like Absorb and Mega-Drain to impress the crowd. If you used strong Poffins you should have no problem winning the contest.