You can’t tell your nafs to do anything, it only seek to fulfill its desires; the nafs does what the nafs wants. You, however have to make it do what you want it to do. You make it get up for Salah even though it doesn’t want to. You make it lower the gaze although it doesn’t want to. You make it stay from the prohibited even thought it’s what fulfills it. You need to discipline your nafs. You have to have control. Lose control, and your nafs will control you. Discipline it. Train it. Form the good habits. Eventually it will weaken, eventually you will manage it. Eventually it will listen. But you have to work, you have to fight your nafs; you have to defeat it lest it defeats you.