To start with a good team in Franchise modedo turn off the salary cap before you start a franchise and select the 'My Madden' option. Increase ALL of your players stats to their maximum and save the roster. Then go to Franchise mode and start a new franchise and if done correctly you will begin the game with ALL of your good players in the team. This trick also works if you trade for good players.
In Franchise mode when ALL Week 17 games (including your own) have been played trade ALL of your draft picks to the worst team in the NFL. When you do this you will recieve the 1st pick of every round instead of whatever you had. This will only work if you have turned the trade deadline off before starting your franchise.
First, make sure that your practice squad is empty. Second, go to the free agents and go to the position you need. Third, sort from youngest to oldest. Fourth, put one of the players on your practice squad. Fifth, a new player with a overall stat of around 50 will appear Sixth, put him on the practice squad Seventh, keep doing that untill your practice squad is full Eigth, check all of stats such as speed, catching, carrying... Ninth pick the ones you want and sign them. Lastly, look in your depth chart, ( these players will now have an overall from anywhere from 75- to around 85) when they progress during the season their overall will shoot up to around 80. This is because one of their stats is zero that does not matter, but it affects overall average. Please rate this if it helps you get a lot of good rookies.
Really creating a player can not be done on this game. But I got the next best thing. Go to the My Madden. Then go to rosters. Once you go to rosters, open the free agents page. Find a player that resembles the player you want to make the most. Sign the player to the team of your choice and then get out of the free agency. Then go to view rosters and click on the player that you got from the free agency. Once you do that you will be able to change his attributes and information to what you want.