umbreon

All you have to do is keep on growing it's happiness. If it grows 2 big hearts grow on it in the MORNING ONLY then it will evolve into umbreon, so be careful.

A few ways of growing happiness:
1. Spa treatment at the resort area (national pokedex needed)
2. Massage at Veilstone
3. First Pokemon in party
4. In party for a long time
5. Not letting it faint
6. Feeding berries for happiness growth.

NOTE:If it evolves at night, it will evolve into espeon.

Ah yes, not to worry, I can help you ^_^

In order to evolve your Eevee into an Umbreon, you need to do a few things. First, you need to increase your Eevee's friendship with you till it reaches it's max level. That means that you need to level your Eevee up a lot, and not let it die. Feed it Vitamins and Minerals such as Proteins, and Zinc, and take it to the woman in Veilstone City for a daily Massage.

After you have done all of that, the only thing you need to do is evolve it into an Umbreon. You can do by simply leveling up your Eevee at nighttime and it will evolve.

In order to get an Umbreon you have to have max friendship with it, two big hearts on the friendship checker. Then once that is done level eevee up between 8pm and 4am. To increase friendshhip quicker, don't llet eevee die, make it hold soothe bell, give it things like protiens, giv it messages.

Hope this helps =)

I think there was a small mix up with the first answer, to get an umbreon you must get it to like you a lot then make it go up one leavel at NIGHT if you make it go up one level in the MORNING you will get an espeon