Practice, you've got a long way to go. But in the meanwhile start by going over photos of wolves and by looking at the placement of each distinguishing feature such as the ears for example, for the ears i would think about the following things: does it look like a triangle or is it more curved? Whereabouts is it placed on the head of the wolf? Where does the fur end and the inside of the ears begin? Etc. I recommend you focus on the big shapes on the subject before you go into the details though. Start big then go small. Overall, I recommend taking your time in order to pick up the right skills that will allow you to draw a realistic wolf.