First! You need to visit this extraordinary website to find a slime chunk, I usually pick the coordinates of a slime chunk that come in pairs (each slime chunk is 16x16 blocks, so that means a pair will be 32x16)
Second! Using your map, you need to dig down to level five, which is the level right before bedrock, and clear out a room that is the length of the slime chunk and at least three blocks high, but if you're like me, I TNT'd a few more spaces to make it longer, feeling that way more slimes would spawn.
Third! To enhance the possibility of even more slimes spawning, go up to level nine using your map and clear out a room that is the exact same length and height as the room you cleared out below it (leaving a block high floor separating the two).
Then, boom, slimes will begin to spawn ONLY if you are in a certain radius near them, but not in the actual slime spawning rooms. Which means you can either dig a tunnel at least 24 blocks away and make a small waiting area or you can do what I did and build your house directly above your slime trap, that way when you check back, slimes will be there waiting for you.
Mind the fact that slimes spawn much slower than regular mobs, and do count as a hostile mob. Meaning they will not spawn on peaceful and you must wait a few minutes before some start spawning.
Second! Using your map, you need to dig down to level five, which is the level right before bedrock, and clear out a room that is the length of the slime chunk and at least three blocks high, but if you're like me, I TNT'd a few more spaces to make it longer, feeling that way more slimes would spawn.
Third! To enhance the possibility of even more slimes spawning, go up to level nine using your map and clear out a room that is the exact same length and height as the room you cleared out below it (leaving a block high floor separating the two).
Then, boom, slimes will begin to spawn ONLY if you are in a certain radius near them, but not in the actual slime spawning rooms. Which means you can either dig a tunnel at least 24 blocks away and make a small waiting area or you can do what I did and build your house directly above your slime trap, that way when you check back, slimes will be there waiting for you.
Mind the fact that slimes spawn much slower than regular mobs, and do count as a hostile mob. Meaning they will not spawn on peaceful and you must wait a few minutes before some start spawning.
http://www.minecraftforum.net/topic/1315731-slimes-and-slime-farms-101