Sometimes, no amount of watching technique being demonsrated is sufficient to do it yourself. You have to have some understanding of a technique before your can even see the sublties present in the movements. If that's the case, how do you learn? Simple - ask questions.
Every school is different. Some instructors do not encourage questions during the class, often because that's the way they were taught. If questions are permitted, don't be afraid to ask about something that you don't understand. This might extend beyond understanding the movements of the technique. You might ask why something is done in a particular way (vs. some other way). You might ask about terminology, since often it's in Japanese, a language foreign to most of us.
Things to Remember
Here are some things to remember when asking questions:
- be polite and respect your teacher
- don't interrupt to ask a question or the answer when given
- try not to ask the same question over now or later
- focus on the answer - don't be distracted by what might be going on around you.
- be concise about the question - your teacher doesn't have time for vague or overly complex questions
Asking Outside of Class
If your teacher feels that asking questions during class is inappropriate, he might be more open about it after class or perhaps in a social situation. Most teachers like teaching and they value an interested and motivated student, so it might be just a matter of finding the right opportunity or setting to ask.
Asking Other People
Sometimes it's easier (and perhaps less embarrassing) to ask questions of your fellow students. Students at your level of proficiency are likely to be struggling with exactly the same things you are. Maybe one of them has figured it out a bit sooner than you. Students slightly more advanced than you are likely to remember the problems that you are facing right now. Finally, advanced students are most likely to have the answers you are looking for.
Regardless of who you ask, you're likely to encounter people who are uninterested in answering you. Perhaps they are too focused on their own training to worry about yours or have another reason. Don't be discouraged by this sort of thing. Ask someone else. In time, you'll learn who is willing to share their knowledge and who won't.