Follow up (a PM)
> I wait 8 - 10 days for it to mature, then I can start staking right?
You do not wait 8-10 days. You wait 8.8 days before entering the "reward competition".
See it that way :
1. There is a 8.8 days "cool-off" period.
2. Then your block start accumulating weight and once it gets more weight than any other in the world (this is examined once every 90 seconds), you'll get a reward
3. Then the block will be divided in two blocks of (original amount+reward)/2, which be stripped of their accumulated weight and coin age
Back to 1 and start again (coo-of, staking, reward, split-and-reset, cool-off)
Update: added to
What is PoS?#2, the highest weight will not automatically be the next to stake. It is statistically the most likely, but since hashing is involved (and a nonce), this makes it a bit more random then that. Or else small blocks would never stake. But as a rule of thumb, the bigger the weight, the quicker the stake.