What is your method for practicing reading a Torah portion and thus memorizing the associated vowelizations and intonations? I'm looking for ideas for maximizing your effectiveness at performing a correct reading when actually confronted with a Torah scroll and for minimizing the total practice time necessary.
My method has changed with time. I don't think that my current method is inherently better, it is just better now for my changed mind. I used to break up an aliya into roughly 1/4 column length segments and practice the whole segment with vowelizations and intonation marks, and then go ahead and try it on the Torah-like printed side. I would go back and forth over that segment until I was comfortable with it (but not necessarily perfect) and then move on to the next segment. When all segments were done, I would go back and try to perfect the aliya as whole.
Today, I just tackle one pasuk at time, perfect it, and then learn the next. Each time I perfect a new pasuk, I rehearse from the top of aliya again. If the Aliya is longer than average or has a convenient breaking point, I will divide it and not return to the top of the aliya, but the top of the sgment, as I go through the process.
For example, I just read two aliyas today in Parshat Mikeitz, the 3rd and 4th, that I previously did not know. With the third, I always went back to the top at the end of each newly learned pasuk. With the forth, I broke it up into two portions. When I got to he point of "VaYar Yaakov", then from there forward I only went back to that pasuk as I learned the remaining versus.
I reached a degree of minimal proficiency° for these two aliyot on one Shabbat Afternoon. For me, that's what works today. There was a time I was more efficient, (and using my older method) but after going back to studying new Torah portions after not having taken on anything new for several years, I found that I just couldn't learn like I used to, both in pace and in method. Through experimentation, I know this is what works best for me at this time. - It may not do anything for anybody else.
Advantages I find to this method now: (1) Taking it a pasuk at a time allows me to quickly commit to memory that one segment. (2) Rehearsing from top as I go along keeps me from forgetting the first pasuk by the time I get to the last.
° Degree of proficiency: The first time through, I may know it on Torah side for that short while and while reading it slowly, and also while correcting myself but without looking back at the vowelizations and intonation marks -- making for a very choppy reading. If I put down the tikun and don't look at it again until the next day then something has been lost... and I need to relearn parts. Then there's the pressure element. I have found that just because I can read it perfectly at home, doesn't mean I won't botch it when I get up to do it in public. It takes me a great deal of rehearsing to be able to go up to the Torah and do it well. By the time I am satisfied with my degree of proficiency I will be able to visualize most of the words with the intonation in my head as I read it. I will also have a bunch of cues that come to mind just by seeing the first couple words of the pasuk (i.e. okay.. here's the one where the first occurrence is "et" and the second occurrence is "ait" or "Paroh and "Pharoh", etc.)
[EDIT BY AARON 12-20-2009] After some more thought (and some sleep) I decided to see if I can formulate and expand what I related above:
(I also do the hand motion thing Shalom mentioned, I don't know if it's a learning aid, or just a left over habit from watching my bar mitzvah teacher as he was trying to get me to understand the nuances of the intonations.)
It is entirely possible that my method is only suitable for myself, but I am happy to share, and if anyone else finds it useful, post about it.
P.S> I never understood Ba'alei Kriya, who are picking up the Chumash between aliyot. At times, when I have not had enough time to practice, I have tried that, and it just doesn't help me. Either I know it cold before I get to shul, or I just don't know it like I should and a last minute scan while hearing the gabbia make a Mishberach isn't going to help one iota. From what I have seen, this holds true for many but not all others... and you know you're likely in for a long leining if they holding the chumash.. particularly if they are holding up the start of the next aliya so they can finish their scan.
This might be obvious, but important to mention: when practicing, use the same names of G-d ("Ad-nai" and not "Hashem", etc.) as in the real reading. It's a legitimate use of the Name.
Some people are auditory learners, some people visual. Occasionally I try to visualize the (absent) cantillation marks onto the scroll I'm reading.
As with any learning experience, the more you involve yourself into it, the more likely it is to stick. When practicing, I read out loud, and occasionally add in hand motions too. (Note: those watching you do this might think you're crazy. Sorry.)
I've seen readers who, in between Aliyot, instead of looking at a printed Chumash, keep the Torah scroll open and read it with their eyes, while hearing the pronunciation in their heads. If you've already practiced a few times, this makes a great last-minute prep to prevent some of those I-knew-it-but-my-mind-blanked errors. Of course, you have to fend off overzealous Gabbaim (and/or Olim) who keep trying to cover the scroll. (Covering the scroll is a way of respecting it while not in use. But practicing with the scroll should be as legitimate a use as any.)
There was a neuroscience paper published a few years ago studying the mental capabilities of several London cab drivers, who have to have the whole city memorized. It would be really neat if someone did something like that with expert Torah readers.
I would suggest drawing up a road map for learning the layning committing to a certain amount of time each day.
For example...if you can learn 30 minutes a day each day until the shabbos of your layning and at that rate it would take you 4 weeks then lay out a schedule of 30 minute days each day.
I have found that when I learn layning the most importan thing is to practice every day so that the stuff that I have already know doesn't escape.
I just wanted to add some other comments that relate to the learning of Torah reading but are not at all related the methodology points of my earlier answer.