You can't put money into a Roth IRA if you don't have income from work. However, your spouse can set up and fund a Roth IRA on your behalf if you still have earned income. Since IRAs cannot be maintained as joint accounts, the spouse's Roth IRA must be in your name, even if your spouse makes the contributions. If your spouse continues to work and has earned income, you can set up and fund a Roth IRA for you, even if you don't work actively.
This marital Roth IRA must be in your name, even if your spouse is the one making the contributions. Since people usually contribute to IRAs throughout their lives and invest at the same time, IRA balances can be quite high when they reach retirement age. When you withdraw money from your Roth IRA later in life, you'll be able to do so without paying any account growth tax. However, you can still contribute to a Roth IRA and make cumulative contributions to a Roth or traditional IRA, regardless of your age.
If you had a SIMPLE IRA or an SEP IRA but have retired from that job, you can still open an IRA through investment firms such as Vanguard or Fidelity. If you are retired and your spouse has earned income, he or she can contribute to their own IRA and also make what is called a spousal contribution to your IRA. An IRA (and its corollary, the Roth IRA) is a tax-advantaged form of retirement account that allows you to save money during your working years so that you can withdraw it during retirement.