Oil burns dirty, what should be done to a winter summer hook-up to prepare for winter?

Not sure I understand what you are asking. Can you give a little more info. Or a lot more info.

If you are asking about an oil burner, you will want to use number 1 diesel for winter. Actually you should use number 1 all the time for an oil burner.

My question is mostly maintenance oriented. I'm using heating oil from the folks I've had servicing my oil burner in the past and they were doing the yearly maintenance for us (for a fee of course). Now that I've been out of work for quite some time I want to know about cleaning the burner and service in general. I've oiled the motor bearing where there's a little cap, that's basic but with the way oil burns I'm thinking there's probably some parts that should be cleaned yearly or periodically. They must have been doing something that what I was paying for.

I would suggest paying for just one more service call, and have them show you what they do for maintenance. A good tech will be happy to show you the basics of the furnace operation, and maintenance. Then you can take over from there. Most likely the fee was more of a warranty to cover parts and repair if the unit failed. Just know that if the unit fails and is not a simple do it yourself fix, it may cost you a bit, or a lot to have it fixed.

If it were me, I would try to locate an install or homeowners manual for the unit you have, and it should tell the maintenance schedule and procedures. It won't get to indepth, just tells basic stuff and mostly will say contact a licensed service tech for any real problems. In all honesty, most people just let the unit run until there is a problem, and then call a tech. However, it is a good idea to find out what you can do to prolong the life of the furnace.