How to create a Blockchain for new alt coin after genesis block has been created? I am creating a new alt coin and I want to know how to generate a Blockchain for that coin. I have already created the genesis block for my new alt coin.
you can try the following steps: 

 bitcoind -daemon # Start bitcoin core
 bitcoin-cli setgenerate true 1 # You've started a new miner!!
 tail -f ~/.bitcoin/debug.log # Track your log

After a while (it depends on the difficulty of your altcoin), a new block will be generated by your miner. 



Check it by typing "bitcoin-cli getblockcount". Every time a new block is genereated, the value increases by one.