Good morning.

I have recently purchased a home, and work from a home office. Right now
the "office" is a roughed-in room in the basement. In addition to sheetrock
and some cosmetic work, it needs electricity. I currently use several
computers, (2) laser printers, plus assorted peripherals. I need to power
these as well as room lighting and general use outlets.

I am comfortable with electrical wiring, and have done a fair amount over
the years. I have never added a breaker, but as I see it - as long as I
turn off the main breaker, avoid the supply lines, and properly size the
circuits, I should be fine. (The house is about 30 years old. Box is 200A.
I assume the electric service to be original.)

Q#1. Are my assumptions correct?
Q#2. How should I split the circuits?
Q#3. How do I go about sizing (amperage) the circuits?

Thanks!