sometimes miss out the ‘I’ subject e.g. ‘Sorry haven’t written before…’ or ‘Don’t know where the time goes…’ or ‘Must stop now, the dinner’s burning’.
use idiomatic expressions or colloquialisms
show off any current slang he or she may have picked up (it’s really cool!)
ask direct questions, use exclamation marks, use checking tags (isn’t it? ) etc
write as if he or she is talking
However, this is an examination and the candidate should also
have a good, organised paragraph structure even for short letters.
show a good range of vocabulary, such as phrasal verbs, which are often considered in English to be less academic or formal.
There are many openings and closings possible in informal letters, depending on the closeness of the relationship between the writer and recipient:
Dear Harry
Dearest Harry
My dear Harry
My darling Harry
Hi Harry! (often used in emails now)
Love from Liz
Love, Liz
With love from Liz
Lots of love from Liz
Best wishes, Liz
All the best, Liz
See you soon, Liz