Take a look at this Hindi in-script key board and follow Hindi letters or upper and lower Roman letters shown in white color on English key board.
http://indiatyping.com/index.php/dow...eyboard-layout
Try to type in Hindi-Phonetically here.
अ आ इ ई ऊ ऍ ए ऐ ऑ ओ औ अं अं अँ अः
a aa i ii u uu a.c e ai o.c o au a.n a.m a.N aH
ट ठ ड ढ ण त थ द ध न
T Th D Dh N t th d dh n
S/ष kS /क्ष jn/ज्ञ
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