When we need help with something, we often turn to our best friend. And if this friend is reliable, they will always be there. 

Be that friend for your client. When the client asks you to update one of your articles, or fix a bug in your code, do it right away. Show them you are reliable.

Plan your projects ahead of time and offer realistic schedules.

Don't repeatedly ask for more time to deliver a project. Ensure that you meet the deadlines.

Freelancers may want to make excuses when clients give feedback. For example, if a client wants you to change the font you've used in a design, don't try to make defend yourself.

There are ways to accept criticism and explain your creative thinking, but that is done through discussion and understanding their expectations.

Keeping a client happy means understanding their expectations.

From time to time, ask how they're doing, if they're satisfied with your work, and if there is anything you can do to improve your work. It shows your willingness to improve and get closer to the client.

You will make mistakes, such as a typo in a product page copy.

Whatever it is, own up to your mistakes and learn from them. If you're unsure how to proceed, ask the client what went wrong or how you can avoid the error in future.

It's fine to apologise occasionally, but if you keep apologising all the time, you will eventually annoy your client. Sorry for the late reply. Sorry, it won't happen again.

If you've made a mistake, try a different approach. "Hi John, I had to see my friend at the hospital yesterday and missed the deadline. I'll deliver the project later today."