When you’re working at your computer and a client sends an e-mail, instead of replying by e-mail, pick up the phone and call them.
Responding by e-mail is faster and easier which is why everyone does it. This is why you should avoid doing it where possible. A phone call will always pleasantly(?) surprise a client.
Example:
“Hi Jane, it’s Warren the photographer. I just received your e-mail about tomorrow’s business portraits. You were wondering how long the photography will take.
“If we can make sure the five people are all on time, we’ll need the use of the conference room for only two hours.
“Setting up and taking down the equipment is very quick. I’ll make sure the room is put back to normal before I leave.
“I look forward to meeting you tomorrow.”