1. How to improve my waitlist chances?
The best way to get into a class is enrolling in a section that is empty/ has the smallest waitlist. For example, let's say Physics 8B lecture has a 50 person waitlist and only a few remaining open seats , but you notice that one of the discussion sections and labs has one available seat. If you enroll in this section, then you will bypass the 50 person waitlist and be enrolled in lecture. This is because if you are enrolled in a section, then by default you are also enrolled in the lecture. If there are no remaining open seats, enroll in a section that has the smallest waitlist (these tend to be the early 8 AM classes) so you will have a higher chance of entering that section and thereby lecture as well. Another aspect to point out is that occasionally students drop a course, and as a result there will be a random open seat in the middle of the summer or winter break, well after Telebears Phase 1. I would frequently checkschedule.berkeley.edu to chase after this; for the most current information, I would click on "Click her for current enrollment information and course information" rather than read the "Avail Seats" section under each lecture which is updated only once a day. I would also check this a few times a day (I was extreme, but because of this strategy, I've always had my schedule of choice), and after a few days to a week I would be enrolled in a lecture or discussion section in the middle of summer/winter break. This strategy doesn't just apply to waitlists; if you are enrolled in a less than desirable section, you can do this to enroll in your discussion of choice. If these tactics don't work, you can also attend lectures for the first few weeks or speak with the professor once the semester starts. Eventually, you will get into the class. Good luck!
2. How to email professors
I generally have a three paragraph template for my emails. The point is to keep it brief, as professors are busy and likely do not want to read walls of text, yet informative about who you are, what you want to do in the future, and why you want to join their lab. In the first paragraph, I introduce myself: "Hi Professor/Dr._____, my name is Christine and I am a third year undergraduate student majoring in Molecular and Cell Biology (Biochemistry.)" I would next describe my career goals and passions in one or two sentences. In the next section, I describe my past experiences and connect them in some way to why I am interested in this professor's research. It is important to read a description of their research online and skim through their papers on pubmed for their current research (we all know lab websites aren't updated frequently.) This way, when you write this important section, you will have concrete material to write about; this also shows the professor that you are genuinely interested and not merely looking for any research position. In the last section, I tie everything together and ask the professor if I can drop by his/her office hours or meet them in person to talk more about their research. It is important to convey your interest in the research, how it is relevant to your goals, and how you can contribute to the professor's research. This is difficult to summarize yourself in a short email, but after a few emails, you will have a familiarity with emailing professors and other professionals as well. Good luck!