Consider your current heading.
With what you know, and what you can reasonably anticipate, where will you end up if you maintain your current course? Don’t like the destination? Change the heading.
If you are comfortable with the destination, check the compass. You can only maintain a heading if your compass works. You also need to know where you are at. This is based on the accuracy of your current information and your ability to interpret it correctly.
Finally, constantly recalibrate. The currents, winds, storms and magnetic deviation introduce variables. Keep track of them and respond accordingly.