I "semi-retired" at about age 51 (I'm now 55ish).

This is what I would recommend that you do, and don't do:

Note: this is not in any order of importance.

1. Do stay active. The more the better. My father used to always say that "everyone he knew died within 5 years or less of retirement" (he, rest his soul, made it past 10 years due to his staying active).

2. Do try to double what you think you'll need finance wise during your retirement.

3. Do not give a financial "power of attorney" to anyone other than your spouse (if you must, you can define a PoA as "limited" which will require your signature on any financial decisions/transactions).

4. Do consider attending various educational classes. You can, of course, do this on-line or at your local adult ed. school or community college (don't worry, you'll probably be surprised at the large numbers of "older" students).

5. Do not spend your newly found spare time buying things on-line or at the store. Stay within your retirement budget.

6. Do spend time managing your finances.

7. Do consider volunteer work. This can a great way to stay active and, at the same time, meet other people.

8. Do not allow yourself to become too settled in with a "day after day" routine. Change things up a bit now and then.

9. Do get out and do as many of the things you told yourself you'd like to do "someday".

10. Don't "wear-out" your favorite hobbies. Consider taking up new hobbies that are challenging. Learning how to play a guitar, piano, or some other musical instrument (as previously mentioned) is a good idea.

11. Do give you and your spouse (if applicable) plenty of space.

12. Do maintain an "I can go back to work" attitude.

13. Do get out and visit with both old and new friends while you still can (I've sadly lost several old friends during the last 10 years).