Open a file on your computer and start writing as your creative thoughts and ideas begin to unfold.
Decide if you are going to design your own novel format using different files and windows, if you are going to download free software or if you are going to invest in a commercial package.
Determine the deadline you are going to give yourself to finish the novel and mark it on a calendar. Even if you haven't quite finished the last chapter by then, it will help keep you focused. Too often, a novel stays on the computer forever as a work-in-progress.
Set up a novel writing schedule. Writing is work and you have to put in the time. So even if you are having writer's block, sit in front of your computer and review what you've written, as it may spark another creative flow.
Back up your work everyday. One of the problems of writing your novel on a computer is that you can lose your "baby" in the flash of a virus. At the end of each day, date and save your work to a USB. Another idea is to create an email account and send your work to yourself as an attachment.