A single, silent e at the end of the word is dropped before ing.
example: come - coming
I am coming home. You are coming home. He is coming home.
But: ee at the end of the word is not changed
example: agree - agreeing
The final consonant after a short, stressed vowel is doubled before ing.
example: sit - sitting
I am sitting on the sofa. You are sitting on the sofa. He is sitting on the sofa.
The letter l as final consonant after a vowel is always doubled before ing.
example: travel - travelling
I am travelling around. You are travelling around. He is travelling around.
Mind: This applies only for British English; in American English there is usually only one l.
An ie at the end of a word becomes y before ing.
example: lie - lying
I am lying in bed. You are lying in bed. He is lying in bed.