"Edit player "must be on in settings. Choose a player you wish to resign before season is over. Go to "edit" player and change his position to punter or kicker regardless of what position they play. IF the computer says the "team will fall below the minimum requirements at the position , You may have to sign a low level free agent at the player's SAME position that you are trying to resign, or you may have a EXCESS player already on your team that you can change their position temporarily. Once you change the position go back and resign the player. The computer will now look at the player as a punter/kicker and you can resign the player for as much as 7 years, no signing bonus, and minimal salary. Once resigning is done don't forget to change the players position back to normal and save it. Beat the cap!
Also if you have the edit player setting on during a franchise season, you can increase any players attributes to increase their overall rating to your liking. Just go to manage player then choose "edit player". From there increase his attributes then don't forget to save the changes. You can make your entire team 99s in franchise mode if you wish.