On Crunchy Squirrel's blog, http://www.crunchytiff.blogspot.com/ there is a three part discussion on how to pick your films for the TIFF. I have a few pointers on other things you should consider.
1) Theatre Size
This is probably the biggest determining factor to whether or not you will get your first choice when it comes to the lottery. Here are the seat counts that I remember from last year's screening guide.
Jackman Hall - 198
Cumberland Theatres - 1 - 213, 2 - 288, 3 - 319, 4 - 164.
Isabel Bader - 452
Royal Ontario Museum - 312
Ryerson Theatre - 1209
Varsity Theatres - 1 - 202, 2 - 226, 3 - 235, 4 - 161, 5 - 126, 6 - 125, 7 - 138, 8 - 580
Elgin Theatre - 1500
Roy Thomson Hall - 2600 (this is for normal performances, quite a few seats are not available for screenings b/c of the sight lines)
Paramount Theatres - I do not know the seat counts, but they are at least 300.
If there is a movie that you are dying to see, for ex. "Sideways", and you are trying to decide which of the two showing you try and pick. Show 1 - Cumberland 3. Show 2 - Ryerson. You have a better chance of getting your selection with a bigger house.
Remember that The Elgin Theatre & RTH have a certain percentage already taken due to the gala passes that are sold.
2) Time & Distance
Rarely are you going to be so fortunate that all your films for the day are at one location. As a result, you have to properly plan your time from one theatre to the next. All the theatres, save the Paramount / Ryerson, are within a block or two of a subway stop. The Paramount is the farthest walk (it normally takes me 10-15 min. from Osgoode). You should give yourself at LEAST 30 min. to get from the Paramount to any other location. The quickest trip for me is from the Ryerson to the Elgin.
3) Star gazer or Film lover
Why are you at the TIFF? Is it a) to see stars or b) is it all about the movies?
a) The stars are not going to arrive at the theatre more than 30 min. before showtimes. Most times it seems it's 5-10 before. Don't kill yourself trying to get to a spot hours in advance.
b) The main Galas are split into 6 p.m. shows and 9 p.m. The 6 p.m. will show the next morning at 9 a.m., the 9 p.m. will show at noon. (approx.) Instead of paying the high cost for the galas, you can save $ and see it the next day. These shows are rarely sold out b/c they are so early in the day. Do not expect to see anyone of note at the 9 a.m. shows. By the noon screenings, you may get to hear from the director.
4) How's your stomach?
Ask yourself how long you can go without food. The Cumberland, Varsity and Paramount are normal movie theatres with the typical concession stands. The Elgin and RTH have a few items (candies, water) for sale. The Ryerson and the Isabel Bader theatre have no concessions.
5) Try Midnight madness
The midnight madness crowds are a blast. They can make mediocre films into cult classics. But pick and choose your films. There is a huge drawback to going to all the films. First, they start to run together. Second, the more midnights you go to, the harder it will be to get up the next day for an early screening.
Have fun. The schedule will be out Tuesday.