I'd recommend budgeting whatever money you'd like to spend out ahead of time and acquire your Bitcoin for the event. (cryptojunky.com)
Until recently, the way that most people acquired bitcoin was via payment for goods or services, by purchasing it through a variety of bitcoin exchanges or by exchanging it with someone directly. (courant.com)
But if you keep a wallet yourself instead of holding your tokens on an exchange, you can also acquire bitcoin on your own. (ibtimes.com)