Apart from the French classes offered by the Institute, you can attend classes organized by the faculty of the University of Geneva. They offer courses starting from the elementary level. From the intermediate level onwards, you can select classes focusing on either grammar, writing or conversation. The registration can be done online usually during the first two weeks of the semester. People on scholarship can attend two courses per semester for free; otherwise, the fees total 250 CHF per semester for one course or 400 CHF, for two. Beware though that many classes are offered only once in a week and that some courses can be very crowded. More info can be found at thttp://www.unige.ch/lettres/elcf/coursappui.html.
For their summer courses, see also www.unige.ch/lettres/elcf/coursete/index_en.html
The Université Populaire du Canton de Genève (http://www.upcge.ch/entree.php) offers French courses for 50 CHF that run from October to June and meet twice a week for 1.5 hours per session. They are open for registration twice a year, but if you decide after registration closes that you would like to join, this is usually possible as well. They test your level and put you in a class that best matches what you know. Courses in other languages, including English, German, Spanish, Italian, and Portuguese, are also offered.
UNIGE offers the option to sign up for language exchange partnerships with other students at the University of Geneva for free. Based on your language preferences for learning/teaching, the system will match you up with other students for language exchange. Information can be found at http://www.unige.ch/tandems/about_en.html.
As some compulsory courses are given in French, be sure to have a good dictionary at hand. An electronic dictionary has the advantage of fast search and in some you can easily add the words you look up to a flashcard database. (Reverso.net is pretty reliable when working on a laptop). Be sure to have audio files included in your dictionary, so that you can learn the pronunciation which is not always easy in French.
If you like studying with flashcards, go for a spaced repetition system, which means that a specific word or phrase will be shown to you in a larger or smaller amount of time, based on how well you remembered it at the last review (you grade it). Anki, for example, is a program that uses spaced repetition, with the advantage of being open-source software and available for many operating systems. The desktop version is for free, the iPhone app costs about 25 CHF. There is a huge database of vocabulary lists for many languages that you can download for free once you have the program installed on your computer, and of course you can create your own database in a very flexible and user-friendly way. It is not only useful for languages, but also for definitions, mathematical formulas of econometrics, remembering the main points of ICJ case law, and virtually anything you don’t want to forget!
For beginners, you can start off with language learning apps such as Duolingo or MosaLingua. Rosetta Stone is also a great learning program (although it is expensive) which makes you learn the language just like a kid learning its mother tongue – not by memorizing grammar rules and vocabulary, but by being exposed to the language in a social context (the software uses tons of photos). It’s particularly advisable for the audio-visual learning type and for languages that are not too difficult. If you want to be able to write Chinese it’s definitely not enough! It’s great up to the intermediate level, but then you have to use other methods.
Since you’re living in a French-speaking city, go out and join clubs and associations (e.g. UNIGE sports clubs, choirs, improv classes), try to meet local people and practice your French as much as possible. Read novels, watch movies (the library of the University of Geneva has lots of interesting movies, besides of course the IHEID library, Swiss Netflix is also a good option), learn French songs by heart, etc. It’s tough to pick up the language at the Institute since we are hardly required to use in in our day-to-day, but knowing French, even just enough to make basic conversation, will definitely enhance your experience in Geneva!