As I mentioned previously, it's good practice to make improvements to your existing village and stabilize your villager population before attempting to move them elsewhere. This includes improving the lighting and adding doors to your buildings. I like to regrade and make proper cobblestone roads to avoid the awkward Mario-Brothers jumping to get around the village.
Construct a mine nearby (but not too close, or your villagers will wander down into it and it will be difficult to get them out). Dig out as much coal and iron ore as you can find. You'll be needing it later.
Minecraft Village Improvements. Adding roads, lighting, and a breeding hut will help your NPC village thrive.
You may want to construct a breeding hut for your villagers. I built a 5x5 square cobblestone building with 2 doors on each side (for a total of 8 doors), which will hopefully turn the population around as I was down to 2 villagers at this point.
Villager breeding depends on how many doors the village has. Minecraft determines what a valid door is by examining 5 blocks in front and in back of the door and calculating how many blocks are hit by sunlight during the day. If the number of "outside" blocks is different than "inside" blocks, it is a valid door. At least that's my understanding of it.
The villager population will increase to a maximum of 0.35 villagers per door. After 21 doors and 10 villagers, an iron golem may appear.
Once you've stabilized your village, it's time to prepare the new village site. I've staked out a 41x41 plot of land for my village (20 blocks in every direction from the center) and clearcut all the trees within that area. You can measure out coordinates by toggling stats with the F3 key. I built another breeding hut in the center of my new village. This is where my imported vilagers will go.
Preparing the New NPC Village Site. The new village will extend 20 blocks in each direction from town center.
Once you've built the breeding hut in the new village, stock up on torches and smelt the iron ore you've collected into iron bars—you'll need it for building rail and a minecart to export villagers to their new home.
Back: Creating a Minecraft Village, Phase 1
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