Hi I got an eevee from a friend and I whant to get a dark eevee and I read..

It's when your Pokemon likes you a lot. As you travel your Pokemon like you more, but if they die in battle they like you less. If you give a Pokemon the soothe bell it decreases the amount of steps you have to take to make a Pokemon like you more.

Basically getting the Pok'emon to like you. Don't let it faint in battle, let it hold a soothe bell, keep it in the front of your party, and feed it Poffin it likes. After that, level it up once(at night, of course), and it should evolve into Umbreon.
You can check how much your Pok'emon likes you by talking to a woman at the Pok'emon club in Hearthome City.

Well you could check on the poketch Frienship checker and touch the pkmn you wanna check and if 2 big hearts show that means it's at high friendship then it should evolve upon lvl up afterwards

Yo,its shonen jump guy.........

Friend ship is how kind you are to your pokemon.you can do this by :
1.never leting your Pokemon faint
2.putting your Pokemon in the front of the party
3.ALLWAYS make sure the Pokemon gets exp.points from every battle

It also helps by seeing the footstep dude on the beach...
If your eevee get the "footstep ribbon" you sould be good to go!!
Hope I helped--seeya!=]

Josecuevo, your response is very inappropriate. In order to get an Umbreon (dark Eevee) you must have high friendship. To get his friendship level high, Battle with him, take a looong strool, (30000 steps should do it) Give it items like Protein and Calcium, and give it a massage from the massage lady. Certain berries also raise friendship at the expense of your evs. Don't let Eevee faint, and don't use herbal medicine. Always have a sooth bell on Eevee until it evolves. Eevee will evole when you build it up a level with two large hearts coming out of the Poketech friendship app.

Refer to my other answer. Please avoid double posting.