Don't Propose Without a Plan: "Follow the Boy Scout motto and 'be prepared,'" Pease said. "Take a critical look at your proposal plan and consider all of the possible obstacles to executing it successfully. In other words, think catastrophically and be a worry wart. Weather and traffic are the biggest potential troublemakers, but a clueless limo driver can also ruin your day.
"If you're planning to propose in your local park and have arranged for a musician to meet you there, do you have a plan if it rains? Popping the question at the top of the Empire State Building? How will you get past security with the ring in your pocket? Make sure that you think through all of the elements of your engagement from the set-up to the actual proposal and to what happens afterwards."
Don't Forget About the Aftermath: "When putting together your engagement plan, consider when you'll be asking her to marry you," Pease said. "Will it be in the morning before she has to go to work? If she's rushed to get to an important meeting, she may not be able to bask in the glow of the moment. If you're camping in the middle of nowhere without a cell signal or in an exotic location around the world, how will you call to share the news with friends and family?"
"Keep in mind that you'll want to be able to ride the wave of being engaged after she says yes, so be sure to take that into consideration when making plans."
Don't Propose on a Jumbotron: Ever.