Remember, practice exercises can be turned in at any time for full credit. Of course, I recommend you do it on time so that you can receive feedback from me in a timely fashion--learning and error correction depends on timely feedback. Practice is the easiest way to practice your skills and improve. Choose to do every assignment, one day at a time, and you will do fine.
Also, when you look at the your grade online and see yourself dropping below 75% or so in the practice/assignment portion of the grade, you might want to change your ways. I advise you to do so because my data suggests that any student who does less than 75% of the practices usually does not pass the course. I have been teaching for more than a decade and I can only think of a handful of students who defied the odds in this regard.
Basically, practice=mastery=high grade in course. No practice=familiarity=lower grade in course. It's quite logical when you stop to think about it .