1 - Try never to mix your busness life with your fanily life, because that can easily lead to a toxic potion. When you are in business mode, be focused on your business. If it means hirering a babysitter to occupy your children while you work, do it.
2 - Make sure you have a business telephone line, a separate fax line, and a third modem line.
3 - Keep yourself as organized as you would if your were working in a corporate office.  Just because you work from your home doesn't mean you are any less of a professional.
4 - Don't set up your computer in a shared space like the kitchen or living room.
5 - Make sure there are no distractions to keep you from focusing on your work.
6 - Set your morning as you were working in an outside office. Wake up early, shower and dress for work before you have breakfast.
7 - Upgrade your hardware - a Fax machine first, then a copy machine and maybe a better telephone system.
8 - Sudden increases, decreases and other AC power disturbances occur daily, which can wreak havoc with your computer and data.  Power-protection devices can save your PC system - and your business.   (UPS)
9 - Have two phones for each phone line - make one  of those phones
10 - Get Caller ID - (enhanced)
11- your main phone should have speakerphone, Redial, HOLD, conferencing.
12 - If you're on the phone a lot - get a head-set to replace the hand-set.
13 - Get a good mapping program - like MS "MapPoint2001"
14 - Get a good telephone number software program, - like "SelectPhone"