What some of the novice players of the Farming Simulator Series don't realize is that most of the achievements and Trophies will actually be earn simply by running and growing a successful farm. Because this reigns truer than ever before in Farming Simulator 18, players should honestly let the achievements come on their own. Again, if you're playing the game as it's meant to be player, all the trophies will flow in without even trying. As the expression goes: "Do what you love and the money will come." In this case, both the money and trophies will come to the expert farmer.
That being said, some of the harder and more obscure Trophies will take some time to earn; you may even need to devote some serious playing time in achieving a few of them. However, should you like to finish your collection of trophies with whatever harder-to-obtain ones that remain, then trying do so after your farm has turned into a business that basically runs itself. After you have enough employees running the farm and making all of your deliveries, you will have plenty of time to complete what achievements that are still needing to be finished.