Henry Gornbein: Prenuptial Agreements: The Good, The Bad and The Ugly

Have an attorney represent you who is experienced in Family Law, especially with regard to drafting and negotiating pre- and post-nuptial agreements.

Make sure that this is discussed months in advance of the wedding and not presented at the last minute.
Be prepared to negotiate and be fair.
Have provisions so that as situations change, the agreement can be reviewed and revised, or else there can be a sunset clause. A sunset clause is one that after so many years of marriage, the agreement is deemed null and void.
I have some agreements, especially in high net-worth cases, that after a number of years, there is a phase-in and a sharing of some of the premarital assets and a sharing or guarantee of spousal support under certain situations.
Be fair. Don't be greedy. Remember the goal is not to get that last dollar, but to try to have a happy and successful marriage. Emphasizing the bad and the ugly will probably lead more quickly to a divorce.