It's important to revoke any powers of attorney on your personal accounts.
If you don't, your spouse may empty them out. A power of attorney gives legal access. Check into canceling any that exist relating to your own bank, securities brokerage and other important accounts.
Additionally, to protect your privacy, have your personal mail sent to your own post office box or mailbox service. Speak to your attorney about transferring any martially related mail there, and changing other addresses associated with your marriage. While you don't want to seem as if you're concealing assets and conducting hidden financial dealings, you still need to protect yourself and want to know about all crucial correspondence. This may have to be worked out between your respective attorneys.
Update your will, health care directives and all other estate-related documents.
If you die unexpectedly without a will, or if your spouse is named as sole beneficiary in your will, he or she will inherit all your assets unless you have children. If you have kids, there are situation-specific laws that determine what your spouse and children respectively receive.
If you don't have a will, hire a lawyer to prepare one now. If you do have one but haven't named a new beneficiary, have your attorney update it with all necessary changes.
Even if you have an updated will, your spouse can challenge it before the divorce is finalized. If you die, he or she is entitled to receive one third of the estate or $50,000.00, whichever is greater. However, you may still want to make changes so that whatever your spouse could receive is limited to these amounts. Again, if children are involved, different formulas may apply.
Similarly, any health care proxy or living will you have in force may need to be revised. These documents allow your spouse to make health care and medical decisions for you, if you are not able to yourself. Many people are not comfortable having these decisions made by spouses whom they are divorcing. If you aren't, appoint someone else.
These issues should be addressed immediately. Don't wait until you reach a final divorce settlement.