“Don't marry the person you think you can live with; marry only the one you think you can't live without.”
— James C. Dobson (Christian psychologist)
Choose the right time of year.
Be sure to discuss with her the approximate time of year you want to be married.
Be sure to propose about 7-12 months prior to the ideal month you'd like to be married. There are many reasons why this much time is important, but a big one is accommodating for the time it takes to order/customize a wedding dress. Trust me, she will not be happy if there's no choice but to take what's on the rack.
Pick the right environment.
Determine if she’d want something public or private.
Determine who will be there.
You know her personality, so be sure to include family and/or friends if she would want them there.
Tell only those who need to know.
Keep it a surprise for as long as possible before you literally pop the question.
Consider getting some hired help... ask for:
-The costs related to time (flat fee or hourly)
-The hard costs (transportation, equipment rentals and other items)
-A complete understanding of your responsibilities
-A signed contract
-Assistance from a hotel concierge/maitre d' (if applicable)
-Resources: Brilliant Event Planning or Go Get It Events
Take notes from those that have gone before you (real proposal videos):
-Top Gun Style
-On A Game Show
-Making The Movies Jealous
-On Stage At A Concert
-Dancing In The Park
-A Billboard Style Mural
-On Live TV
-In The Middle Of Disneyland
-Staring In Your Own Movie
-A Serenade On The Subway