When you turn 65, you become eligible for the Medicare program — which means you will need to set aside time around that milestone birthday to sift through many options so you can sign up for the coverage that meets your health needs and budget.

It’s up to you to get ready. No letter will arrive in the mail announcing it’s time to start making these decisions. What’s more, the timetable is specific and extremely important. You can start signing up three months before you turn 65, and you’ll have until three months after your birthday month to enroll. If you miss that deadline, you may end up paying higher premiums. If you are still working and have employer-sponsored health coverage, you can probably wait to sign up.

You’ll need to do some homework before you start assessing options and picking plans. Make a list of your doctors and decide how important it is to you that you can continue seeing them once you are on Medicare. Also, make a list of any medications you take so you can make sure any prescription drug plan you select will meet your needs.

Think about your lifestyle. Are you a homebody and never travel outside the U.S.? Or are you an adventurer who travels abroad often? Do you split your time between residences and need medical care in different states? All these factors will figure into the decisions you make.

Your financial situation is also important. Medicare helps pay for medical care for most older Americans and also people with disabilities. But it’s not free. You’ll want to choose an option you can afford and build the array of out-of-pocket costs into your annual budget. And take time to review the ways the federal government can help you pay Medicare’s costs if you can’t afford them.