In order to keep this awful, awful scenario from happening to you, The Rock Lock Company was born. Chris Goulet turned a bright idea into a product you can buy, with this here buckle simply snapping around your guitar neck, looping around something immobile and locking into place. Of course, you'll need a tech to remove it prior to rolling out for your first song, but it's probably worth the $49.99 asking price for all those other moments. Hit the source link to get your pre-order in, but only if you enjoy free shipping as a bonus.
Rock Lock guitar security tool