Any time you want to call time out, but don't want to waste time by doing it the long way, just push start in the huddle (where you select your play book).
Infinite Trades
Set the game mode to trade schedule and enter. Do as many trade weeks as you wish, then reset the Genesis. Go to Regular Season, then Game Start. You will have all the players you traded, but will start from Trade Week one if you enter the free-agent area. If you reset after Trade Week one, you will start at trade week two.
Old-School Players
Go into regular season. Do and finish a season to the point where the Super Bowl is over, then select game start and you will see a screen that says "try next season". Then select the teams you would like to trade with and select game start again. Then you will go into another trade week. Get your trade weeks over. Start and finish a new season. Repeat this procedure until you see an american flag and credits. Go to free agents area and there will be players in the free agent area like Joe Namath presented as QB Jets and many others.