Learning these basic commands is an imperative for the success of Skijoring, as it would ascertain that your dog obeys you completely.
Line out, this would make the dog walk to the end of the gangline, so as to even out any slack on the line. It's important that this command is taught first. If your dog isn't further away from your skis, then it's at a risk of injury.
Hike, this command cajoles your dog into moving forward or running. Now, which dog doesn't love doing that?
Gee (Left) and Haw (right), these commands are important to provide directional input to your dog's movement. You wouldn't want your dog to run unabated, wouldn't you?
Whoa, this command would make your dog stop, and impede further movement.
Don't be shy about asking someone who's a veteran of Skijoring. After all, they would have also committed all the mistakes that you would, as a beginner.
Skijoring could be quite a lot of fun. If done correctly. Make sure you put your safety before everything else, and remember, don't chase! No matter how tempted you are to do so.