If the system of learning Sanskrit is to be natural and the process of learning is to be smooth and enjoyable then we would recommend to base the learning process first of all on listening and repeating.
So the live flow of the language is the first step. To that we attach the meaning of what we listen to and what we repeat, and based on that we can proceed to reading and writing. Only then, after a while, we would go into the grammar - and that too, in a very gradual and simple way.
When we study like this the heart and the feeling come first, then the head and the intellect. First we experience, then we understand. Live flow of the language is of utmost importance - on that we can build the understanding of the meanings, and then the knowledge of grammar becomes easy to grasp.
The best way, of course, would be to learn from a teacher who can speak Sanskrit. Listening to the teacher and repeating is the ideal process. Then the teacher will guide us through the meanings and grammar also.
If such a teacher is not available then we would recommend working with recorded texts. If recorded lessons are not available (soon we will upload some basic lessons to this website...) then one can easily find (on the Internet) texts, as well as recordings of well known works (like the Bhagavad Gita, Yoga Sutra etc.).
In the beginning - if you study on your own - just listen to the recordings - it will be very useful. Then listen and try to repeat. Just listen and repeat. If you are not sure of your pronunciation get a friend to listen to you and correct you by comparing your pronunciation to what She/he hears on the recordings.
In the next step listen and try to repeat with the help of the transliterated texts. When your pronunciation is fluent enough start reading without listening to the recordings. While practicing reading and correct pronunciation it is good to start learning the Devanagari script (a lot of learning material on Devanagari is available on the web, and soon we will also upload some detailed lessons here...)
The learning process should be very effortless. For example, in the Sanskrit lessons that we teach the first lessons contain text and recordings of simple sentences in Sanskrit with translation. The practice is just listening and repeating. No effort to memorize, no difficult explanations. Just audio recordings to listen to and to repeat - supported by transliterated text and translation.
As we progress, sentences quickly become stories and conversations, and previously learned lessons are more deeply explained. The structure of the language reveals itself naturally, and is dealt with in accordance with the experience in assimilating the live flow of the language.
We should emphasize again that by recommending the system of learning to be natural and simple we do not mean that it should neglect the study of grammar. We simply say that we should not approach grammar as the basis for the study of the language, but rather the language as the basis for the study of its grammar.
As the students assimilate the flow of the language understanding of the rules of grammar would become easier. Another point is that the more we present the grammar in a lively and practical manner the more easily it is digested. In our lessons for example, we use stories, rhymes and flow-charts, in order to create a holistic understanding of the principles that structure the language.
When the study of the language is based on such principles then the learning process will be enjoyable. From the beginning, the live flow of the language will be assimilated along with a growing ability to pronounce, read, and understand the ancient scriptures.