puppeth is a command-line tool that comes with geth. It can help you create a new Ethereum network, down to the genesis block, bootnodes, miners, and ethstats servers, in a user-friendly way. Start puppeth using the following command:

$ puppeth

You will be asked to enter a network name. You can either enter a new network name or use the one that you already created using puppeth. Once you enter it, you can see the list of things that puppeth can do. 

Create a new genesis file using puppeth and use Proof of Authority (clique) as the consensus algorithm. Try creating a private network with the generated genesis file.