deriv LSK ETT STT aSTA ALPH OLDHOMEPAGE NEWHOMEPAGE
In the traditional spelling of Sanskrit, there are no spaces at all. Wherever the writer intends the reader to make a pause when reading aloud, a stick or double stick is placed. Basically the stick is used at end of sentence and the doublestick at end of paragraph. In manuscripts they didn't start a new line after each paragraph — which made sense because birch bark and bhoja leaf were expensive.
The exception to that are stanzas. You must use a stick after all verses except the last one, that gets a doublestick. Writing a stick in the middle of a verse is forbidden, even if the author intends a pause there, and it must be spelled as if the reader made no pause — see mid verse hell.
In printed books, when using Indian letters, spaces are added after a /pada when they don't look too ugly. They look too ugly —
(A) after a pada that is ibc
sarvabhUteSu सर्वभूतेषु
(B) after a consonant that is not /M /H
hanumAMstiSThati हनुमांस्तिष्ठति
(C) after a /pada created by svAdiSvasarv...
manobhiH मनोभिः
(D) when the same vowel belongs to two padas.
rAjovAca राजोवाच
Oddly, spaces do not look ugly before an enclitic —
kiJ cit किं चित्
rAmo vA sItA vA रामो वा सीता वा
When using Roman letters, you may place spaces after all consonants.