Confidence

To finish any project you need to work at it. If a book is the project, it is like anything else it needs to be done often to become good at it. As you write, you will improve. And confidence in your writing will come also. Writing must be a everyday activity even writing about day to day things if you cannot think of anything to write because your head is so full of everything else. Just write to that you can improve.

Guilt

Do you feel guilty for wanting some time to write? Handling guilt over writing instead of chasing the kids around the house or helping them with homework is tuff. You need to admit your faults and move on. Read Admitting Your Faults And Using Them.

Finding Time

How do you find the time to write? Decide to do things right away. Open mail when you get it from the mail box. Read the paper or throw it away. When going through your email choose to read your mail, throw it out, put it in a pending file, or forward it. You may have more choices that you want to make but the point is go through it and get rid of it or save it. Make decisions quickly, you already have all the information you need to make a decision. Make the decision and move on.
Get over your guilt, find the time to write, and confidence will come.