When it comes to transfer season, go to the transfer market and search for 'free agents' with a skill level above 85. If you happen to find one, make a very large offer on their wages, so they will accept. After your next game they should have accepted, then put them up for sale straight away. After your next game, someone should have made an offer on them, and voila, you've made big bucks.

Anderson came up as free agent from man united, I got him and sold him for 40 million to arsenal, sweet!