What does it take to succeed in this dive?
Like studying any foreign language, to succeed with Malayalam, you will need to spend a lot of time reading, writing, speaking, and listening. These four skills together will help you to master Malayalam. 
This requires lots of practice and perseverance since Malayalam has the most number of letters of any Indian language. The easy part of Malayalam is the vocabulary as Malayalam has quite a few words borrowed from Sanskrit. This of course assumes that you know some Sanskrit!  The hardest part is probably the pronunciation, as mentioned earlier, and of course, learning the many letters.t
For those who really wish to master the language, you should make the commitment to make the pursuit of Malayalam a lifelong hobby.  Every day, more and more people are learning Malayalam, so it will be time well spent. 
You will have to find good study materials, good teachers, and good practice partners. Most importantly, you will have to find the discipline to study and practice and improve regularly. If you don't study regularly, you won't make much progress, or worse, you'll make lots of progress and then forget what you've learned! 
The secret to fluency (since we know you want to know) is quite simple: master reading, master writing, master speaking, master listening, improve your pronunciation, and improve your vocabulary. The issue is that most people don't actually do any of these tasks well. 
You see, most people only focus on one or two of these skills, or they focus on all six, but at a very cursory level. If you wish to become fluent, however, you need to focus on all six, all the time, and spend enough time with each so that you see regular progress. 
Bottom line, if you want to become fluent, do this: 

  1. Read 20 minutes a day in Malayalam, and from varying sources 

  2. Listen to Malayalam TV and radio every day 

  3. Write a new essay or short story every week and get it corrected 

  4. Speak weekly with others, and ideally those who can correct your mistakes 

  5. Make sure your pronunciation is as spot-on as can be 

  6. Improve your vocabulary constantly.

Do these things regularly, and within 4 - 7 years, you can almost certainly become fluent in Malayalam. The question is: will you actually do these things? Ahh, that is the question. We hope you will!