If you are wanting to actually play through the game. Then just keep playing. If you are an average player you should be able to do it within two seasons. The better you are the faster you can do it. Expect it to take more than one season to do. you do not have to get all the things on the list to get legend. you can double up on some to make up for those you dont get.
yeah casue i go undefeated and still takes 2-3 years before Im inducted.