A proposal is a very special thing. It is the beginning of a beautiful life together.
When considering a proposal, try to think of fond memories that allowed you to go from being friends to wanting to propose marriage.
For example. If a couple met at a certain place or restaurant and they haven't been there in a long time, this is the perfect time and place to propose because it takes you back to what attracted you to each other in the first place.
Human behaviour allows us to reach into our past and when we re-live fond moments, it puts ourselves and the other person at ease and causes them to remember the good and respond in kind.