I'm assuming you have the geth console installed.

In a directory of your choice unzip the following file
Test Server
This will create a directory named testServer

move into the testServer directory and initialise geth with this command


geth --datadir data init genesis.json


then start geth with


geth --datadir data --networkid 20160720 --ipcpath < path to ipc file> console 2>geth.log


replacing < path to ipc file> as follows :

~/Library/Ethereum/geth.ipc for Mac
or ~/.ethereum/geth.ipc for Linux
or ~/AppData/Roaming/Ethereum/geth.ipc for Windows

If you start geth with the ipc flag, then your Ethereum wallet will connect to your geth instance and hence the private network which is useful but not necessary

You should then be connected to the private network and you will see block synchronisation

If you are using the wallet you can use the GUI to create accounts and contracts
otherwise
in the geth console you can create an account with
personal.newAccount()
then start mining with
miner.start()


If you want to use rpc and unlock your account you can run


geth --datadir data --networkid 20160720 --ipcpath < path to ipc file> --rpc --rpcaddr=localhost --rpcport=8545 --rpccorsdomain "*" --unlock 0 console 2>geth.log