The first trading method is Tech Avion Rare or Non Rare.
This involves picking up low cost cards from the top 5 leagues with meta stats and listing them for 300 coins above buy price.
The best players to do this method with is players with High pace. See image of players that have been successful below.
List cards for 300 more than purchase price. Example Buy for 400 list for 700. Buy for 500 list for 800 etc…
Check the players cheapest price then mass bid just under cheapest buy now.