If you have a sprout then plant it immediatly. If you wait the sprout could dry out and die. Plant it in any size container you have availible, but do not use anything that is clear. Plant the sprout, taproot down, just below the surface of the soil. The taproot is the white "tentacle" looking thing, you want this facing down.
Don't worry you will get the hang of it, all it takes is time and patience. Oh...and reading 420mag Grow forums.
If the seed is cracking that means it is on it's way to showing the taproot. You should at that point just put it back in the germination bag and wait another day or two for the taproot to emerge.
Do not use clear containers because the roots like darkness. If you use a clear container the roots will cluster towrards the center of the soil and stay away from the outer edges to avoid the light. You want to make as much use of the size of the container that you have and also want the roots to spread out unhindered.