How would you boost a child's self esteem?

By encouraging them in what they do.

All dai, Everi day, Bng bng!

also do not put them down, comfort them when they are sad, do not praise them for every small achievement because they notice when you are not treating them like every one else and try not to get to angry with then and don't be patronising.

i know this because i had very low self esteem as a child.