You do some research to see if parts are available--are they ones you
can get at any dealer or do you have to find a company that reconditions
old ones or makes new ones using old molds, or do they have to come
from overseas, etc. You need to have room to store and work on the car
and have the tools--metric, English, US all have different sizes. Get a
copy of the owners manual, too but don't expect it to tell you
everything you need to know. Join a car club for your car, hopefully
local. But you find a car you love and just start working on it. You do
a little bit at a time. Just be sure to have some place to keep it
while you do. It's great to get one running no matter how rough it
looks and don't think you have to have loads of time and money to get
involved.