If your goal is to retire at age 65 - make it real easy and start saving for retirement at 35 or 40 so time is on your side.

Want to retire at 50? Start saving as soon as you leave college (yes in addition to paying off student loans, saving for a house, saving for your baby's college expenses, buying that new SUV, etc.). The sooner you start saving, the sooner you can retire. The more you save now, the more money you will be able to spend later.

Retirement saving should be one of your top priorities once you get out of school. Figure out where your income will come from in retirement, and when retirement will be affordable and work optional.  Spend some time going over the numbers.