1. How well is a good enough school performance?
You do not have to be a straight A student. For most of you, feeling comfortable to ask three professors for recommendation letters is good enough, and necessary.
2. How to ask for a recommendation letter?
You don't "ask" for a recommendation letter, you EARN a recommendation letter through answering and asking questions in class, discussing your career goal after class, asking advice and giving feedback, or performing well in competitive exams. At least, make sure instructors can remember your face when you ask for a recommendation letter.
3. What is a bad question?
A bad question is the one whose answer can be easily searched out on the syllabus, website or slides. Put differently, a cheap question is a bad question. Always try to ask a question that it is hard to get the answer somewhere else.
4. What is a good question?
Using an example to check if you fully understand the main concepts is a good question, and it always benefits your classmates.
5. What kind of student do professors like to associate more?
Professors are more likely to associate students who give feedback about their instructions, like what you learnt from the reading list, if some methodology works, etc.
6. What you want to know before applying to a graduate school?
The placement of previous students in departments you plan to apply is always important to know. This information can be found on departments' websites, or through your network.
Talk to current students, ask whether they get enough help in the departments, and how many students quit. If someone quits, it's a strong signal that your life can be tough there.
7. How to get advanced in your career?
Ask seniors what skills are necessary, and practice as early as possible, like oTree in experimental economics.