Take it with you and walk with it , but it will take time!
You have to finish the hoenn dex another way is to trade the purified croconaw from Pokemon colosseum then just get an egg hatch it and you have totodile.
Put them in your party with Slugma/Marcargo, this pokemon's body heat will warm the egg and make it hatch faster.
Use the Bicycle plus a Pokemon with Flame Body or Magma Armor as their ability. That will reduce the steps required to hatch an egg.
It depends on the egg your hatching, but its usually around 2,000 - 5,000 steps. The fastest way to hatch it is to literally ride on your bike (: -Chii Magmar + Bike your egg will hatch within 5-10 mins.
The best way to hatch Pokemon eggs is to cycle from solaceon town to twinleaf town and back .Or cycle up and down seabreak path
You get a certain Pokemon that cuts the steps you walk but it depends on the old versin of black or the new versin
Well, the way I get taillows is to breed two swellows, and hatch the eggs. The eggs take around 3000 steps to hatch. The taillows evolve into swellows at level 20-22 as far as I know.
The best way is to use a Pokemon with Flame Body or Magma Armor as their ability, it reduces the number of steps required to hatch the eggs (they do not stack with each other or themselves). Have a Pokemon of one of these abilities in your team as you cycle along a long route such as the routes above and below Solceon and Cycling Route.
The only way to get it is from Pokemon emerald or Pokemon colosseum.
In Pokemon games, hatching doesn't actually depend on time, but on the amount of steps you take. So, if you run from one city back to another over and over again... that will cause the eggs to hatch quickly. It it sort of boring that way, so if you just want to play the game normally you can hatch eggs that way too... but for me, I usually want to hatch a bunch of eggs at once, so I have one Pokemon and 5 eggs in my party and I just run up and down until they hatch, one by one. Then I switch out the hatched ones for more eggs until I'm done.
No you cant catch Latios in Pokemon Colosseum. You can only trade it in from your Ruby or Sapphire game in to the Colosseum game and that's the only way you can get it.
You can never release an egg. You have to hatch it and release the Pokemon inside. If it's a bad egg then don't hatch it or it'd kill your game. You're pretty much stuck with the bad egg unless you didn't save after you took it. Though, if you have My Pokemon Ranch for the Wii, then you can deposit the eggs and never have to withdraw them that way...