With email, what can be misunderstood will be misunderstood. That's why you should be double careful with everything you write.
Take Another Look Before You Send a Message
One strategy to avoid misinterpretations is to
- allow every message at least some minutes of rest after you have finished it but
- before you press the "Send" button.
Reread and reconsider the whole message when you return to it, possibly from the recipient's perspective.
It never fails to amaze me how many ambiguities I manage to work into short and simple emails.