Please watch the video 'What Are Diacritics - Introduction' first; then watch 'What Are Diacritics - Vowels' and then watch this one.
Part 1 is here: Sanskrit Pronunciation
Part 2 is here: Sanskrit Pronunciation
How to pronounce the vowels and consonants: Sanskrit Pronunciation
My heartfelt gratitude goes to HG Padma Sambhava Prabhu of Auckland who guided me in the principles of Accelerated Learning and who came up with the first version of these Romanized Sanskrit Alphabet Charts which greatly help students to easily recognize the PATTERNS in the alphabet tables. This format of presenting the alphabets to beginners makes it so much easier for them to grasp and recollect what the diacritics are, where they appear and what they mean in terms of sound. (Because we are so pre-conditioned by the normal roman alphabets, our mind auto-deletes all the diacritics as we read and that makes it hard for beginners to notice and understand the diacritics. The exercise of drawing out these charts a few times cements the understanding of the diacritics position and the related tongue positions and sounds.)
Thanks also to HG Vaishnava Seva Prabhu of the Bhaktivedanta Hospital, Mira Rd East, Mumbai, whose sincere inquiry inspired me to finally make these simple lessons available online. Hare Krishna!
I have collected my sanskrit pronunciation course resources on one page now on our Gita Jayanti Int'l Network on gitajayanti.ning.com - here's the easy-to-remember shortcut for it:: http://tiny.cc/sanskrit