Never send a boring 'hey' or a dry 'gm' again. Start her day off right with texts that make her smile.
Instead of just saying 'good morning', add a question or a tease. For example, 'good morning, what's the most exciting thing you have planned today?' gives her something easy to answer.
If you are in a relationship, daily morning texts are normal. If you are just dating or crushing, sending one every single day can feel a bit clingy. Mix it up.