1) DECIDE YOUR AUDIENCE
Throwing a bunch of mails to the clients who aren’t interested in your services, hardly make any sense. And sending such mails 100 or greater in a day is useless.
Instead send 20 or less mails to the specific people, will definitely give you one deal and chances of getting leads will increase perhaps.
Firstly do research work, accumulate receivers mail data and then send accordingly.
2) SUBJECT LINE IS ONE PLAY GAME
Imagine you’re a sweet lover & got a mail whose subject line reads “purchase sweets from our shop”. Don’t you think it sounds boring & I’m sure you aren’t going to open the mail even.
Instead if it would came like ” Had hectic day? Don’t worry! Wrap up with some delight in your tummy.”
In above both examples, the motive is same i.e., to sell sweets but the way of putting them is totally different.
This is all. You must write a subject line as if it attracts the reader in one glance & left with no other reason than opening it.