Before migrating your contract, don't forget to make sure that Ganache is running. If not, keep the same configuration file, truffle.js, as in the earlier example, and run Ganache as we did before: ganache-cli -p 7545.
Ganache will mine blocks instantly, but you can pass in a blocktime to delay block creation to be able to track what’s happening. The block time is set using the -b option followed by a number (delay in seconds).