Caroline Gibson wrote a useful piece for The Professional Copywriters' Network about how to get paid. A few of her points are below alongside thoughts of my own.
Have clients agree to your terms.
It’s important to clarify terms before money changes hands, because the more that both sides know what to expect, the smoother your projects will tend to run.
Specify the payment date.
Not personally applicable because most of my projects are split into two payments — the first is requested before I schedule the work, and the second upon completion, before final artwork is supplied. I tell clients in advance how long the work will take, but I generally don’t give an exact date because it depends on the speed of client feedback.
Get partial payment upfront.
50 percent in advance is standard for a lot of designers I’ve spoken to. For me, that’ll sometimes change depending on the project scope and the money involved. If I do a quick job for a new client I'll need 100 percent in advance, but if the project is larger than the norm I’ll sometimes invoice for less than 50 percent.
Keep track of when payments are due.
After I send a final invoice I set a reminder to contact the client in three weeks if payment isn’t received. My terms include a late payment charge after 30 days, so it’s courteous to remind my client before the charge is made. I can’t remember the last time I had to chase up a client, though, mainly because I don’t send artwork until the last invoice is paid.
Avoid international bank charges.
It’s your call if you want clients to pick up the cost of a wire transfer. I recommend adding it to your terms if the project cost is small (in the hundreds).
A commentator on Caroline’s post advised using a separate accounts@ email address for sending invoices and payment reminders. Nice tip, but more applicable for those not working independently.
Here’s the full post.
And another worthwhile read from the same writer: Invoice payment well overdue? Here’s what to do next.
“When you’re offered a very low budget by a very huge client, you can always feel good about turning it down knowing that you are helping to raise the standards of pricing for others.”