A few things will make this easier to help you.
Do you have concerns (something is wrong), suggestions for improvement, general thoughts you want to share, or something else?
Is this person a potential partner in the proposal? A customer? A vendor? A co-worker? Is there a power dynamic between you where he is your superior, or you are his?
Without knowing any of that:
To follow up on our earlier phone conversation, listed below are my thoughts on the proposals we discussed.