Nintendo Pokemon Y Electronic Manual

To evolve Eevee into Sylveon, increase its affection to at least two hearts in Pokemon-Amie and ensure it knows a Fairy-type move. Then level it up.
Use the Pokemon Bank app to transfer Pokemon from Black, White, Black 2, or White 2. Then, use the Poke Transporter to send them to Pokemon Y.
Visit the Boutique or the Salon in various cities to change clothes, accessories, or hairstyles. The first available location is in Lumiose City.
If the game freezes, perform a soft reset by pressing L + R + Start or Select to restart the game without turning off the console.
Increase happiness by walking with the Pokemon, using items like Soothe Bell, feeding them vitamins, and avoiding fainting in battles.
The HM for Surf is obtained from Calem/Serena in Shalour City after defeating the Shalour City Gym Leader.
Access the Player Search System (PSS) on the bottom screen and select Wonder Trade. Choose a Pokemon to trade and wait for a random trade partner.
Super Training is a feature that allows you to increase a Pokemon's EVs through mini-games. Access it via the touchscreen and select a training regimen.
Shiny Pokemon are rare, but using methods like the Masuda Method or chaining with the Poke Radar increases the chances of encountering them.
Ensure the cartridge and slot are clean. If the issue persists, try inserting a different game or consult Nintendo support for further troubleshooting.