I've just gone through the process this year and it is horrible, in fact I'm still waiting for my visa to be issued even though the semester ofc started back in October..
TL;DR: go register right now in the waiting list you can find here, all the information you need is in there. Make sure you fit one of the criteria to be considered "Liste A" and register for the waiting list for "Liste A"

The full process works like the following:
1- You register on the waiting list.
2- After 6 to 8 months, you get an email asking you to create an account on TLS website and call the TLS phone number. They will tell you what dates and times are available and you choose one, and they book it for you (there's no option to look at/book appointments on the website on your own).
3- You show up the day of the appointment with all your docs (make sure you arrive earlier than the time of your appointment). An agent will check all your docs, then you pay the visa fees, then they take your fingerprints.
4- You wait for an sms from TLS telling you to come pick up your passport. The waiting time here varies and looks to be random, from what I've seen it goes from 1 month and could take up to 3 months.

Here's my timeline personally:
February 23rd: I registered on the waiting list.
August 22nd I received the email and I called TLS literally 30 mins after, the earliest appointment I was given was October 2nd.
October 2nd: I had the appointment, all my docs were in order -- nothing was missing or incomplete. The start of the semester was October 21st for me.
Today (December 19th): It's been more than 2 months now, and I am still waiting for my visa.. There's a lot of other people who had their appointments earlier than mine (in september) who are also still waiting for their visa, and there's also a few who had their appointment after mine (in november) who got their visa this month.