Professors are human. They can be kind and supportive or bitter and vindictive, like it or not. Grin and bear it or switch classes. Or get to know what your prof wants. Studies show (PDF, 3 pgs) that getting to know them improves your chances of success in college.
Understand them. It's key to your success, as it can lead to mentoring from them, which is valuable if you plan to do graduate work. Sitting near the front of class improves your chances of catching little hints and participating in lectures.
Think like a professor. Most professors say it takes about two minutes of preparation for each minute of lecture. Participate in the learning process by previewing topics before a lecture. If you want to go a step beyond, understand what a lecturer has to consider when preparing exams, assignments and term paper options.
Your professor has a job and a life. Do approach them for help, but do it during their designated office hours. Lecturers have a memory for students who don't display respect, and it can affect your mark in the long run.
Use the Google, be the Google
Put in the effort. Make it look as if you cared about it enough to organize your paper. Write a good introduction and make it clear what you are writing about.
Don't use online term paper mills
Not picking a good study spot
Not reviewing lecture notes
Leaving things to the last minute
Not meeting the assigned word count
Using someone’s work and not citing it
Utilize your resources: attend seminars and labs
Get to know your university’s library
Talk to the teaching assistant
Check the official course website